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    Editorial
    Depression and Anxiety – Separate or Continuum?
    Siegfried Kasper   162


    Reviews/Mini-reviews

    Antidepressant Drug Discovery in the Postgenomic Era
    Florian Holsboer   165

    Psychopharmacogenetics - a Challenge for Pharmacotherapy in Psychiatry
    Brigitta Bondy, Peter Zill 178


    Original Investigations/Summaries of Original Research

    The Activity of b-Hexosaminidase (uHex) and g-Glutamyltransferase (uGGT) in
    Urine as Non-Invasive Markers of Chronic Alcohol Abuse: I. Alcohol-Dependent
    Subjects
    Ewa Taracha, Bogu slaw Habrat, Piotr Woz´niak, Jerzy Walkowiak, Bogdan
    Szukalski     184

    Inositol Treatment has no Effect on the Dexamethasone Suppression Test
    Joseph Levine, Uri Leventhal, Vadim Lerner, Robert H Belmaker 190


    Viewpoints

    Obsessive Compulsive Behaviour in Autism - Towards an Autistic-Obsessive
    Compulsive Syndrome?
    Ruth Gross-Isseroff , Haggai Hermesh, Abraham Weizman 193


    Letters to the Editors

    Launch of the Cardiac Safety in Schizophrenia Group (CSISG)
    Dora Kohen 199

    Reponse to Dr. S. Curran and Dr. K. Matthew's Letter to the Editor (World J
    Biol Psychiatry 2001, 2: 107) Concerning Yaryura-Tobias et al (2000) Negative
    Outcome after Neurosurgery for Refractory Obsessive-Compulsive Spectrum
    Disorder, World J Biol Psychiatry 1: 197-203.
    José A Yaryura-Tobias       199

    Case Reports/Case Series

    A Display of Hypomania in a Depressed Male in Response to Fluvoxamine
    Toshihiro Horiguchi, Shinkei Sai 201
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  World J Biol Psychiatry (2001) 2, 162 - 163




  Editorial
  Depression and Anxiety – Separate or Continuum?

  A large proportion of psychiatric illnesses are comprised of depression and anxiety and these two
  conditions demonstrate a considerable overlap of clinical symptoms and pathophysiological
  processes. A large US study found that 58% of individuals with a history of depression also suffered
  from an anxiety disorder, and a study by the World Health Organization (WHO; World Health
  Organization 1999) showed that depression and anxiety were the most common co-existing
  psychological problems in primary care. The occurrence of co-morbid anxiety and depression is a
  significant sign for poor clinical outcome and prognosis, and furthermore for increased social and
  psychological impairment. Despite the overlapping symptomatology the question arises whether or
  not anxiety and depression can be identified as separate illnesses.

  From a neurobiological point of view, most research has been done on serotonin (5-HT) and
  norepinephrin (NE) neurotransmitters, both of which are implicated in anxiety and depression, and
  new evidence suggests that these systems may provide a mechanistic link between the two
  conditions. It could be that the two systems are able to modulate each other, with changes in one
  system being reflected in the other. This would have the clinical implication that a compound with
  a primary serotonergic or noradrenergic mechanism of action would demonstrate therapeutic
  efficacy. Although there is still uncertainty regarding the neurobiological cause, it is known that
  both depression and anxiety are associated with a dysregulation in the serotonergic and
  noradrenergic systems.

  The assumption that depression and anxiety are closely linked is supported by the fact that they
  exist at higher rates than would be expected by chance. Ressler and Nemeroff (2000) reviewed the
  available data and summarised that depression and anxiety are associated with increased NE
  transmission and reduced 5-HT transmission, however, this does not seem to be univocally accepted
  and is sometimes viewed as over-simplified.

  Pathophysiological studies have indicated that elevated levels of NE are associated with somatic
  manifestations of anxiety, such as increased pulse rate, increased blood pressure, dry mouth and
  cessation of intestinal peristalsis (Birkmayer and Riederer 1989). If the neuroadrenergic firing rate of
  the locus coeruleus is increased with drugs such as yohimbine, symptoms of anxiety appear, whereas
  with drugs that reduce the noradrenergic firing rate (e.g., clonidine) anxiety symptoms are reduced
  (Grimsley 1995).

  On the other hand, the serotonergic system has been associated with certain aspects of depression
  and anxiety (specifically with alterations in appetite, energy, sleep, libido and cognitive function)
  (Laird and Benefield 1995). Depletion studies, on the other hand, have shown that decreased levels
  of 5-HT are associated with depression (Delgado et al 1992; Neumeister et al 1998). An increase in
  the serotonergic system with the administration of selective serotonin reuptake inhibitors (SSRIs)
  has been shown to effectively treat depression as well as anxiety and is nowadays regarded as first-
  line treatment in most countries of the world (Pollack and Marzol 2000). Dual-acting anti-
  depressants, such as venlafaxine and milnacipran, inhibit the neuronal uptake of both serotonin
  and NE and have been shown to work in depression as well as in anxiety. Interestingly, there are
  some studies which indicate that dual-acting antidepressants demonstrate a better efficacy in these
  indications compared to compounds that only exert a primary mechanism of action on either NE
  or 5-HT.

  The available psychopharmacological data lead to the suggestion that depression and anxiety are
  controlled by the "balance" of 5-HT and NE, rather than their "absolute" levels. This could mean that
  anxiety and depression are associated with abnormalities in the regulation of these neuro-
  transmitters and that the peripherally measured neurotransmitters or changes obtained with brain
  imaging techniques on the serotonin transporter only reflect a peripheral sign of an as yet unknown
  underlying process. The balance theory is supported by the fact that Raphe nuclei and the locus
  coeruleus are interconnected and mutually inhibitory. This could mean that 5-HT and NE are impli-
  cated in depression and anxiety due to their role in modulating and being modulated by other
  neurobiological systems, and that either one of these neurotransmitters initiates a cascade of events
  which begins with states of anxiety and gradually evolves into depressive states (Paul 1988). This
  assumption would be supported by the fact that generally patients experience anxiety symptoms or




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  diseases with predominantly anxious symptomatology earlier in their lives than depression. On the
  other hand, 5-HT dysregulation could predispose to NE hyperactivity resulting in increased
  depressive symptoms. Kendler (1996) emphasised the fact that either General Anxiety Disorders or
  Major Depression can only develop if environmental factors are also present in addition to the
  biological factors, however, depending on the course of the illness, environmental factors play a
  lesser role in the later stage of the disease.

  For both clinicians and researchers in either the epidemiological or the biological field it is
  important to notice that anxiety and depression show a large overlap of clinical symptoms and
  pathophysiological processes. The consequences of the co-existence of anxiety and depression
  means that patients have a reduced response to treatment, worse prognosis, and increased social and
  psychological impairment. Biologically oriented research mainly focuses on either anxiety disorder
  or depression alone to obtain homogeneous groups. It would be interesting to study the co-morbid
  conditions from a biological point of view and, of course, studies are also awaited which study
  individual patients during a longer course of illness to demonstrate changes in the underlying
  biology that are apparently caused by the disease itself or/and the occurring treatment modalities.
  Studies in co-morbid conditions of anxiety and depression could help understand the interplay and
  homeostasis of the 5-HT and NE systems and contribute to our understanding that probably the two
  conditions, anxiety and depression, are different expressions of the same underlying neurobiological
  disorder.

  Siegfried Kasper

  Correspondence:
  Siegfried Kasper, M.D.
  Professor and Chairman
  Department of General Psychiatry
  University of Vienna
  Währinger Gürtel 18-20
  1090 Vienna
  Austria
  Tel: +43 1 40 400 3568
  Fax: +43 1 40 400 3099
  E-mail: SK@akh-wien.ac.at




  References                                                             tics: The clinical use of drugs. 6th Ed. Applied Therapeutics Inc,
                                                                         Vancouver, British Columbia, Canada, pp 1-28.
  Birkmayer W, Riederer P (1989) Understanding the neuro-
  transmitters: Keys to the workings of the brain. Blau K (translator)   Neumeister A, Praschak-Rieder N, Heßelmann B, Vitouch O, Rauh
  Springer Verlag, Vienna, New York.                                     M, Barocka A, Tauscher J, Kasper S (1998) Effects of tryptophan
                                                                         depletion in drug-free depressed patients who responded to total
  Delgado PL, Price LH, Miller HL, Salomon RM, Aghajanian GK,            sleep deprivation. Arch Gen Psychiatry 55: 167-172.
  Heninger GR, Charney DS (1992) Neurochemistry. In: E. Paykel
  (ed) Handbook of affective disorders. 2nd Ed. Guilford Press, New      Paul SM (1988) Anxiety and depression: a common neuro-
  York, pp 219-253.                                                      biological substrate? J Clin Psychiatry 49 (Suppl): 13-16.

  Grimsley S (1995) Anxiety disorders. In: L. Young, M. Koda-Kimble      Pollack MH, Marzol PC (2000) Pharmacotherapeutic options in the
  (eds) Applied Therapeutics: The clinical use of drugs. 6th Ed.         treatment of comorbid depression and anxiety. CNS Spectrums 5:
  Applied Therapeutics Inc, Vancouver, British Columbia, Canada, pp      23-30.
  32-49.
                                                                         Ressler KJ, Nemeroff CB (2000) Role of serotonergic and nor-
  Kendler KS (1996) Major depression and generalized anxiety             adrenergic systems in the pathophysiology of depression and
  disorder - same genes, (partly) different environments – revisited.    anxiety disorders. Depression and Anxiety 12 (Suppl 1): 2-19.
  Brit J Psychiatry 168: 68-75.
                                                                         World Health Organization (1999) "Composite International
  Laird L, Benefield W (1995) Mood disorders I: major depressive         Diagnostic Interview (CIDI), Version 1.0.". WHO, Geneva.
  disorders. In: L. Young, M. Koda-Kimble (eds) Applied Therapeu-




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  World J Biol Psychiatry (2001) 2, 165 - 177




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   REVIEW/MINI-REVIEW

  Antidepressant Drug Discovery
  in the Postgenomic Era
  Florian Holsboer
  Max Planck Institute of Psychiatry, Munich, Germany

  Summary                                                     The size of the problem
  The progress made in genome research raises the             National surveys conducted in Germany and in
  question whether the new knowledge bases that have          the United States agree that depression and rela-
  emerged may also lead to better antidepressants. The        ted disorders are among the most common me-
  past has seen many remarkable improvements over             dical conditions worldwide (Table 1). It is impor-
  traditional drugs, but not a real breakthrough. More        tant to note that depression is not a by-product
  recently hypothesis-driven research in depression has       of the presumably stressful lifestyle in industrial
  focussed upon stress-hormone regulation as a                countries. In fact, the vulnerability to suffer from
  possible target, but validation of new drugs is not yet     diseases of the central nervous system, including
  in sight. In parallel, we see an upsurge of systematic      depression, may even be enhanced in poor coun-
  unbiased research in a biotechnology-driven drug            tries where malnutrition and infections make
  discovery effort. This research can only lead to results    the brain more susceptible to any kind of nox-
  if clinical research adapts to these new demands by         ious interference. A study by the World Health
  phenotyping depressed patients not only according to        Organization (WHO) calculated that depression
  psychopathological characteristics but also by              will soon become the second leading cause of
  utilising functional (e.g. neuroendocrine, neuropsy-        disability, trailing only ischaemic heart disease.
  chological, neurophysiological, neuroimaging and            These calculations, however, do not fully recog-
  clinical drug response) data that are to be correlated      nize that depression has a large range of adverse
  with data from genotyping.                                  effects on health in general. This is best illustra-
                                                              ted by studies showing that depression is a risk
  To achieve the goal of genotype/phenotype-based             factor for coronary heart disease mortality
  differential therapy, large-scale efforts with regards to   (Glassman and Shapiro 1998; Musselman et al
  both patient samples and genotyping capacities are          1998). A recent study conducted in Amsterdam
  needed. In the long term, increasingly detailed             showed that compared to non-depressed cardiac
  patient information, if translated into specific            patients, the relative risk of subsequent mortality
  pharmacological treatments, will lead to customized         was three times higher for those cardiac patients
  drugs and thus to a partial fragmentation of the            with major depression (Penninx et al 2001).
  antidepressant market. Concurrently, the improved           Likewise the point prevalence of depression
  genotyping/phenotyping efforts will also lead to more       among patients who have recently had an acute
  widely applicable drugs that promise to avoid side          myocardial infarction is around 20% (Carney et
  effects and refractoriness and also to hasten the time      al 1995). Among these cardiac patients the pre-
  to onset of action. Once these goals are achieved           sence of depression is a significant predictor of
  notorious undertreatment of depression may come to          mortality within a six-month observation period
  an end.                                                     (Frasure-Smith et al 1993). In the latter study it
                                                              was shown that the presence of symptoms of
  Key words: depression, functional phenotyping,              major depression multiplies the risk to die due to
  genotyping, proteomics, antidepressant drug                 a cardiac cause by a factor of three to four. While
  discovery.                                                  the mechanism underlying depression-induced
                                                              increase in cardiac mortality is still unclear, it is
  Correspondence:                                             obvious that depression is a complicating factor
  Prof. Florian Holsboer, M.D., Ph.D.                         in coronary artery disease. In this light it is even
  Max Planck Institute of Psychiatry                          more striking that depression is still an under-
  Kraepelinstr. 2-10                                          diagnosed and undertreated disorder. Yet the
  80804 Munich                                                most dramatic implication of depression is the
  Germany                                                     risk of suicide, which is the second leading cause
  Tel: +49 89 30622 220                                       of death among the Western population up to
  Fax: +49 89 30622 483                                       the age of 40, trailing only accidents. The above
  E-mail: holsboer@mpipsykl.mpg.de                            figures also reflect the enormous burden that
                                                              depression and other affective disorders impose
                                                              upon our social system. Other factors, which are
                                                              difficult to estimate, are socioeconomic losses
                                                              due to depression-related absenteeism and poor
                                                              job performance.

                                                              Another alarming figure emerged from a recent
                                                              survey conducted by researchers of the Max


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   REVIEW/MINI-REVIEW

  Planck Institute of Psychiatry in Germany: One                 pation, blurred vision, dry mouth, sedation and
  out of five patients seen by a general practitioner            sexual dysfunction to potential analeptic effects.
  suffers from an affective disorder, but only half              While all these adversities are reversible, they
  of these cases are diagnosed and only 25%                      limit patients' compliance and, even worse, in
  receive appropriate treatment (Wittchen 2000).                 case of intentional or unintentional overdose the
  When combining direct costs such as inpatient                  old drugs may be lethal. The toxicity of tricyclics
  and outpatient care, and pharmaceutical and                    may also occur when they are prescribed to-
  talk therapies, with lost productivity and its con-            gether with drugs that inhibit those liver
  sequences on life-time earnings, it becomes clear              enzymes (e.g. cytochrome P 450 2D6) that are
  that depression takes a major share of the overall             responsible for tricyclic metabolization. Under
  health care expenditures.                                      such conditions even commonly prescribed do-
                                                                 sages may result in steeply increasing, often
                                                                 toxic, circulating plasma antidepressant concen-
  Table 1                                                        trations. Thus, the new generation of drugs that
                                                                 selectively block reuptake of serotonin, nore-
  Life-time prevalence of affective disorders                    pinephrine or both, without interfering with
                                                                 other neurotransmitter receptors, provides a
  Diagnoses                                         Per cent     major advantage. Because of the much lower
                                                                 incidence of adverse effects a more aggressive
  Manic-depressive disorder                         1.0          dose escalation can be administered which may
  Dysthymic disorder                                3.0          hasten the time to onset of clinical action.
  Major depression                                  14.8
  Generalized anxiety disorder                      3.0          Despite this progress, it is perplexing that 40
  Obsessive compulsive disorder                     1.9          years of intense research have not profoundly
  Panic disorder                                    1.5          changed the clinical profile of current anti-
  Social phobia                                     13.0         depressants. The time to onset remains a major
  Simple phobia                                     11.0         challenge, often taking several weeks or months
  Posttraumatic stress disorder                     7.6          until clinical improvement (i.e. until the drugs
                                                                 start working). The similarity of clinical profiles
                                                                 of available antidepressants, however, does not
                                                                 entirely come as a surprise, since the pharma-
  Current antidepressants                                        cological principle, i.e. enhancement of sero-
                                                                 tonin and/or noradrenaline neurotransmission,
  There is hardly any group of drugs in medicine                 has remained unchanged since its first discovery
  that is more capable of successfully treating the              in the case of imipramine. In the absence of
  respective clinical conditions than antidepres-                substantial experimental evidence that depres-
  sants. In fact among the top 10 medicines                      sion and other psychiatric conditions responsive
  ranked according to revenues, three are anti-                  to antidepressant medication (e.g. dysthymia,
  depressants (Prozac® from Lilly, Paxil® from                   social phobia, anorexia, panic disorder, obsessive
  GlaxoSmithKline and Zoloft® from Pfizer). These                compulsive disorder, etc) share a pathophysio-
  three drugs have captured around 80% of the                    logy directly linked to impaired serotonin and/or
  antidepressant market estimated to account for                 noradrenaline metabolism, it was argued that
  eight billion Euro in 1999 and to be growing                   the primary mode of action of these drugs is
  annually by 10%. Remarkably, all three best-                   quite remote from the actual neurobiological
  selling antidepressants belong to the class of                 process leading to symptom resolution (Holsboer
  selective serotonin reuptake inhibitors (SSRIs)                2000). This view is in line with the long time to
  whose pharmacology is not unlike the historical                onset and further underscored by a double-blind
  prototype compounds, the tricyclics imipramine                 controlled study conducted at the Max Planck
  and amitryptiline. These serendipitously dis-                  Institute that compared the antidepressive effect
  covered compounds and a large number of simi-                  of paroxetine (Paxil®, an SSRI) with that of
  lar compounds all rely upon the principle of                   tianeptine, a drug which enhances the presynap-
  enhancing neurotransmission through biogenic                   tic serotonin reuptake transporter, thus working
  amines (serotonin, norepinephrine) by inter-                   opposite to SSRIs. Both compounds, paroxetine
  fering with the presynaptic transporter that                   and tianeptine, had comparable clinical effects,
  reimports the neurotransmitter from the synap-                 further supporting the hypothesis that modu-
  tic cleft once released from presynaptic nerve                 lating biogenic amine neurotransmission pro-
  terminals. The classic tricyclic compounds were                vides only a very non-specific intervention regar-
  much less specific, representing a kind of "single             ding post-receptor effects on the signalling
  molecule polypharmacy" working on a manifold                   cascade (Nickel et al, Unpublished Observation).
  of different receptors. In the absence of a clear
  pharmacological target for depression such an                  One unresolved issue in today's antidepressant
  unspecific mode of action might have a ratio-                  pharmacotherapy is the frequently observed
  nale. The downside of the non-specificity,                     failure of an individual patient to respond
  however, is a wide spectrum of adverse effects,                during a current episode to a drug that was bene-
  ranging from cardiotropic actions through obsti-               ficial when she/he was receiving it during a


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  previous episode. Whereas it may be accepted                          ever, the paucity of totally novel therapeutic
  that different pathological mechanisms may                            leads is remarkable and offers many incentives
  underly different clinical phenotypes, among                          for drug discovery in the coming decades.
  patients it is hard to understand that a depressive
  syndrome in the same patient underlies a dif-                         Hypothesis-driven antidepressant
  ferent neurobiological pathology from episode                         development – stress hormone regulation
  to episode, changing a former responder to a                          as target
  specific drug into a prospective nonresponder.
  This is particularly puzzling as the pharma-                          Enhanced secretion of stress hormones has long
  cological specificity of a certain drug wanes over                    been recognized as a frequent neuroendocrine
  time. In other words, a drug with a specific mode                     symptom among depressed patients but its asso-
  of action after acute treatment becomes non-                          ciation with causation of depression had been
  specific after long-term administration. For                          negated until the isolation and characterization
  example, a specific reuptake inhibitor of sero-                       of corticotropin releasing hormone (CRH) by
  tonin also modulates NE reuptake after chronic                        Vale et al (1981). This neuropeptide was found to
  administration. One possibility has been raised                       elicit not only the hormonal response to stress,
  by Uhr et al (2000), who have shown that the                          i.e. release of ACTH and in turn of glucocorti-
  blood-brain barrier contains P-glycoproteins that                     coids, but also to induce manifold behavioural
  act as extrusion pumps for xenobiotics such as                        changes appropriate to adapt to a stressful situa-
  antidepressants. These findings submit that the                       tion. When injected into the rat or monkey
  activity of the multidrug resistance gene coding                      brain CRH produces behavioural effects that are
  for P-glycoprotein may become differentially                          reminiscent of affective disorders, primarily
  regulated by different drugs over time.                               depression and anxiety disorders. Similarly,
                                                                        when an extra gene coding for CRH is inserted
  Thus, while the newly developed antidepressants                       into the mouse genome, CRH is hypersecreted
  represent a significant improvement over the                          rendering these animals hyperanxious (Stenzel-
  classic tricyclics, they are not fundamentally                        Poore et al 1994). Likewise rats selectively bred
  innovative with regard to their pharmacological                       according to high anxiety have increased CRH
  mode of action.                                                       expression in several relevant brain regions
                                                                        (review: Holsboer 1999). Studies using targeted
  If one recognizes that it currently takes over 600                    mutagenesis revealed that the anxiety-like beha-
  million Euro and 10 years of development until                        viour induced by CRH is conveyed through the
  a drug is approved for marketing, it does not                         CRHR1 receptor subtype, which is not only
  come as a surprise that industry has favoured a                       present on pituitary corticotrophs releasing
  risk-avoiding strategy and developed drugs that                       ACTH, but also in many brain areas believed to
  are only minor modifications of what already                          be involved in generating fear and anxiety. Spe-
  proved successful. This attitude has been fos-                        cifically, mice with a genetically deleted CRHR1
  tered by the enormous opportunities of a rapidly                      receptor show less anxiety-like behaviour and a
  growing antidepressant market. As a result, how-                      reduced hormonal response to stress (Timpl et al



       RESPONSE/
       RELEASE
                   T               T+P




                                                         FIRING RATE




                               Neuropeptides such as CRH are only secreted
                               at high firing rate or bursting activity




  Figure 1
  Frequency dependence of response and release of transmitter and peptide:
  Difference between release of neurotransmitters T (e.g. norepinephrine or serotonin) and neuropeptides P (e.g. CRH) (modified from
  Lundberg and Hökfelt 1983).


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   REVIEW/MINI-REVIEW

  1998). To rule out that this behavioural effect is                    related clinical conditions. All these considera-
  secondary to hormonal actions, a conditional                          tions led us to attempt validation of our basic
  mouse mutant was generated by us where the                            research results and therefore we conducted a
  CRHR1 gene disruption is limited to the frontal                       first-exposure-to-patients experiment with one
  brain. In these mice anxiety-like behaviour is                        of these new compounds (R 121919/NBI 30775)
  also decreased, even though their peripheral                          and administered two different dose escalation
  neuroendocrine system remains intact. All these                       regimens to patients with major depression
  experiments supported the possibility that                            (Zobel et al 2000).
  blocking the CRH/CRHR1 signalling pathway
  may provide a pharmacological opportunity to                          The observations made in this explorative study
  ameliorate stress-related clinical conditions.                        were encouraging: The drug was safe and well-
  Several pharmaceutical industries generated a                         tolerated and even at the highest dosage
  series of nonpeptide compounds that after oral                        administered, the patients were able to secrete
  administration pass the blood-brain barrier and                       ACTH and cortisol at a normal rate when
  bind selectively and with high affinity to CRHR1                      challenged with intravenous CRH, supporting
  receptors. Rats from a strain with high innate                        that they maintained their humoral stress res-
  anxiety proved particularly suited to test the                        ponsiveness when under CRHR1 receptor
  pharmaceutical potential of these chemical com-                       antagonist treatment (Zobel et al 2000). Also all
  pounds. Keck et al (2001) showed that only the                        clinical chemistry and other laboratory and
  "high-anxiety" rats respond to one of these com-                      medical signs and symptoms remained unaffec-
  pounds (R 121919, NBI 30775) with reduced                             ted. The most interesting finding was that in
  anxiety-like behaviour, while among those with                        both treatment panels a significant improve-
  innate low anxiety a CRHR1 receptor antagonist                        ment of depressive symptoms was recorded,
  is without behavioural effect. This supports the                      which was in the same range as documented
  notion that, in contrast to biogenic amines                           from our historical comparison databank of
  (serotonin, norepinephrine etc.) or aminoacids                        patients treated at the Institute with Paxil®
  (GABA, glutamate etc.), neuropeptides are only                        (Figure 2). Two other observations were also of
  hypersecreted under pathological conditions                           interest: The group treated with the higher dose
  (Figure 1). Thus, drugs targeting the former sys-                     regimen produced more responders and after
  tems, i.e. GABA-channel modulators such as                            discontinuation of drug intake all patients,
  benzodiazepines, always have an effect (i.e. an-                      responders and nonresponders, experienced a
  xiolytic, sedative or hypnotic). In contrast, a                       transient worsening of their depressive sympto-
  neuropeptide receptor antagonist produces only                        matology. In addition, in all patients an
  effects when the neuropeptide generating neu-                         improvement of the quality of sleep was repor-
  rons are hyperactive. Thus, theoretically, a                          ted and objectified by sleep-electroencephalo-
  CRHR1 antagonist only has effects when CRH                            graphy; this agrees with a study by Lancel et al
  neurons are hyperactive, which is postulated to                       (In Press) who showed that among stressed rats
  be the case in major depression and other stress-                     with innate high anxiety a CRHR1 antagonist


       Depression Score (BDI)                                                    Depression Score (HAMD)

  35                                                                        35
                                                   End of                                                                    End of
                                                 Treatment                                                                 Treatment
  30                                                                        30

  25                                                                        25

  20                                                                        20

  15                                                                        15

  10                                                                        10

   5                                                                         5

   0                                                                         0
       screening       day 10       day 20        day 30 day 32                  screening      day 10        day 20         day 30 day 32

  Figure 2
  Changes of the Beck Depression Inventory (BDI) (left) and the 21-item Hamilton Depression Rating Scale (HAMD) (right) during NBI
  30775/R 121919 and paroxetine treatment. Drug-free patients were enrolled in two dose escalation panels. In panel 1 the dose range
  increased from 5-40 mg (diamonds) and in panel 2 from 40-80 mg (circles), each within 30 days. Panel 2 resulted in a response rate
  (50% reduction of initial depression severity) that matched that of SSRI paroxetine (historical data of patients matched according to age
  gender and severity of depression who received 20-40 mg paroxetine under clinical drug study conditions). In both panels, HAMD and
  BDI rating scales worsened after discontinuation of NBI 30775/R 121919. Data are means ± SEM (from Zobel et al 2000).



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  may have benefical effects upon the quality of        behaviour, an effect that is blocked by NK1-
  sleep. Plasma or urine assessments of HPA             receptor antagonists (Teixeira et al 1996). Micro-
  activity did not predict response to NBI 30775/R      injection of substance P into other brain areas,
  121919, which is important because CRH hyper-         however, may also induce opposite effects
  activity in central nerve cells mediating affective   (Hasenöhrl et al 1998). In the study by Kramer et
  symptoms is often thought to be concurrently          al (1998), which was the first to submit
  reflected in increased CRH release from the           antidepressant effects of an NK1-receptor
  hypothalamus into portal vessels, leading in turn     antagonist, vocalizations in guinea pigs were
  to elevated plasma ACTH and cortisol levels.          prolonged after administration of an NK1 anta-
  Most basic and clinical studies were conducted        gonist (GR 73632). This was interpreted by the
  with the CRHR1 antagonist R 121919 NBI 30775,         authorship as indicative of a depressogenic effect
  whose further clinical development was dis-           of substance P mimetics, such as GR 73632.
  continued because at very high dosages liver          These NK1 agonist-induced vocalizations were
  toxicity was observed in two healthy probands.        attenuated by a short-term pretreatment of the
  It is noteworthy that this effect is not a problem    guinea pigs with an NK1 receptor antagonist.
  associated with the pharmacological principle of      Similarly, ultrasound vocalizations of neonatal
  CRHR1 antagonists, as such CRH receptors are          mice separated from their mothers were de-
  absent in the liver. Several other pharmaceutical     creased in mutants with targeted deletion of the
  companies are now pursuing this new pharma-           NK1 receptor. Such decreasing effects on voca-
  cological principle with back-up compounds and        lization were also achieved by antidepressant
  once issues on potential toxicology are resolved      treatment (Rupniak and Kramer 1999). A sup-
  we await validation studies on larger samples.        pression of NK1 antagonist elicited vocalizations
                                                        was further induced by acute pretreatment with
  Innovative antidepressant pipeline                    imipramine and fluoxetine in guinea pigs, which
                                                        led Kramer et al (1998) to conclude that NK1
  • Substance P (NK1) receptor antagonists              receptor antagonists have behavioural effects
  Substance P is a member of a family of peptides,      comparable to those of standard antidepressants.
  collectively termed tachykinins, whose main           These observations, however, do not allow one
  physiological action, in contrast to bradykinins,     to extrapolate the similarities in the guinea pig
  is the contraction of smooth muscles. So far          assay used to depressive psychopathology and
  three tachykinin receptors (NK1,2,3) have been        antidepressive treatment effects in patients. Spe-
  identified and substance P preferentially binds to    cifically, antidepressants exert their effects only
  the NK1 receptor subtype. The major interest in       after long-term treatments. Indeed, when imi-
  their neurobiology focused upon their role in         pramine or the SSRI zimelidine are administered
  nociception. Both substance P and NK1 receptors       for two weeks to rats, substance P increases in
  have a widespread distribution in the human           various brain areas, whereas the expression of
  brain (Nomura et al 1987; Chawla et al 1997),         the genes coding for substance P in basal fore-
  including many loci in the limbic system (e.g.        brain structures in rats is not changed after long-
  amygdala, hypothalamus, septum) and the brain         term treatment with a variety of antidepressants
  stem (locus coeruleus, raphe nuclei), supporting      (Stout et al 1999). Studies of regulation of stress
  the view that substance P and its receptor may        hormones have provided insight into the
  play a role in causality and treatment of depres-     mechanism of depression in the past, and most
  sion. Such a possibility was underscored by a         data agree that various stressors might elicit
  clinical trial that reported antidepressant effects   increased syntheses and secretion of substance P
  of MK-869, an NK1 receptor antagonist, that were      (Nussdorfer and Malendowicz 1998). As outlined
  equal to those of paroxetine, an SSRI. Moreover,      above, CRH plays a key role in coordinating
  in this study with 213 patients randomly              physiological response to stress. In this light it is
  assigned to the NK1 receptor antagonist, placebo      interesting that substance P suppresses hypo-
  or 20 mg paroxetine, NK-869 had a side-effect         thalamic activity of CRH neurons. If such an
  profile equal to that of placebo and superior to      interaction would also take place in brain loci
  that of paroxetine (Kramer et al 1998). This          that mediate the behavioural effects of CRH,
  report prompted re-evaluation of previous pre-        then it is difficult to reconcile the postulated
  clinical data and initiated manifold new studies      antidepressant effect of NK1 receptor antagonists.
  all destined to provide a new biological basis of     Such treatment might result in enhancement of
  understanding about how an NK1 receptor               CRH/CRH-receptor signalling, particularly if one
  antagonist expected to be an analgesic may            considers the neuroanatomical proximity of
  ultimately act as antidepressant.                     both pathways. Also warranting a clearer picture
                                                        are the possible effects of NK1 receptor anta-
  Behavioural studies probing substance P/NK1-          gonists upon monoamine neurotransmission.
  receptor signalling have not yielded a clear          McLean et al (1991) showed that when injected
  picture. Nevertheless, several interesting findings   into the locus coeruleus, substance P results in
  emerged pointing to a role of this pathway in         an increased firing rate through activation of
  mediating affective symptoms. When substance          NK1 receptors. This points to the possibility that
  P is injected into the intracerebroventricular        NK1 antagonists act in a similar way as anti-
  (icv) space in rodents it produces anxiety-like       depressants in diminishing locus coeruleus


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  responsivity to all kinds of stressors. An inter-                   Taken together, in contrast to the situation with
  action of substance P and serotonergic neuro-                       CRHR1-antagonists, where a well-founded
  transmission is suggested by the documented                         hypothesis prevails and clinical data are only
  innervation of the raphe nucleus by substance P                     preliminary, the clinical database established for
  immunoreactive fibres. Some studies suggest                         NK1R antagonists is much more robust, while
  that enhanced substance P/NK1-receptor signall-                     basic science-derived evidence for antidepressive
  ing increases serotonergic neuron firing through                    effects is still poor.
  dorsal raphe nucleus activation. Such an effect is
  at variance with the postulated antidepressant                      • Neuropeptides
  effect of NK1 receptor antagonists because                          As proteins are drug targets, a straightforward
  common antidepressants, as well as impairing                        strategy would be to embark on protein-protein-
  CRH1 receptor function, enhance serotonergic                        interactions and use proteins as drugs. This
  neurotransmission.                                                  possibility is limited because efficient delivery of
                                                                      proteins into cells in vivo can be achieved only
  Current basic science-derived evidence sup-                         when the molecules are small – typically less
  porting an antidepressant mode of action of NK1                     than 600 Daltons. Delivery of a peptide across
  receptor antagonists is limited. The initially                      the blood-brain barrier is limited by the size (six
  reported antidepressant effect of MK 869 was not                    amino acids or less) and the biochemical proper-
  corroborated in a subsequent trial and several                      ty (highly lipophilic) of the proteins. Although
  drug companies have developed other NK1                             advocated by some, circumventing this problem
  receptor antagonists and brought them into                          by administering these drugs intranasally using
  their clinical development programmes. Prelimi-                     the vomeronasal organ as a "leaky interface" does
  nary analysis of some of these trials yielded                       not resolve the issue as nerve cell delivery
  positive as well as less optimistic results. From                   remains a problem. A series of synthetic small
  the clinical science perspective it is hoped that                   peptides that are administered subcutaneously
  establishment of a solid neurobiological research                   and reportedly enter the brain were tested in
  basis providing insight into the mode of action                     animal models of depression as well as in
  of these new drugs is not spared just because of a                  patients with depression, and promising data
  series of clinical trials whose majority favours an                 emerged from these preliminary studies.
  antidepressant efficacy. It is this author's impres-
  sion, which is also underscored by the enormous                     The problem with size and lipophilicity restric-
  increase of the antidepressant market revenues,                     tions necessary for delivery can be overcome by
  that a new generation of clinicians as well as our                  utilizing so-called protein transduction domains
  patients increasingly accept drug treatment                         (Figure 3). These are amino acid sequences (10-
  modalities provided that research-derived expla-                    16 residues long) which, when fused to a pro-
  nations of the mechanism of action become                           tein, allow transduction through all membranes
  available.                                                          in a receptor- and transporter-independent




                                                                     Cargo, e.g. GHRH

                                 TAT-PTD
                                                                                    HIV-1 TAT:

                            A                                                       Tyr-Gly-Arg-Lys-Lys-Arg-Arg-Glu-Arg-Arg-Arg

                                                                                                     NLS



                                                                                    FUSION PROTEIN
        Membrane
                            B
                                                                                        TAT       GHRH




                            C
                                           Denatured
                                            (inactive)
                                                                      D                             Refolded
                                                                                                    (active)
                                                             Chaperones

  Figure 3
  Schematic representation of how linking of a protein (cargo, e.g. growth hormone releasing hormone, GHRH) with a protein transduction
  domain (PTD) enables passage of a cargo protein through cell membranes.


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  fashion that appears to target the lipid bilayer       a patient's genetic information with his or her
  directly (Schwarze et al 2000). Thus, once a           response to a certain drug. If a sufficiently dense
  protein is identified as a potential drug target a     SNP map is used, it is not required that the actual
  fusion protein can be constructed that contains        genes or allels involved are identified. Since
  a protein transduction domain and interacts            linkage disequilibrium appears to extend over
  with the protein target. Provided the concern          approximately 30-60 kb (at least in Northern
  that transduced proteins induce immuno-                European populations), the SNP pattern would
  genicity can be ruled out, the possibility to use      be sufficient to predict drug response or side-
  transducible proteins as drugs to deactivate           effect profiles (Roses 2000). The Munich Anti-
  certain cellular components of signalling path-        depressant Response Signature (MARS) project
  ways is tempting.                                      illustrates the basic requirements needed to
                                                         conduct pharmacogenomic studies: Patients
  Pharmacogenomics of affective disorders                need to be characterized on a psychopatho-
                                                         logical level that extensively covers all aspects
  The human genome sequence will provide a               from early trauma, course of illness, previous
  reference for measuring DNA sequence variation         responses, life-events, genetic load as well as
  in human populations (Venter et al 2001; In-           functional manifestation such as neuro-
  ternational Human Genome Sequencing Con-               psychological performance, sleep-electroence-
  sortium 2001). Variants in the genome account          phalography and neuroendocrine parameters
  for the genetic component of individuality,            (see Figure 4). During an antidepressant treat-
  including disease susceptibility and response to       ment course, drug levels need to be monitored,
  drugs. Most genomic variation is attributable to       as well as changes in medical and laboratory
  single nucleotide polymorphisms (SNPs, pro-            signs and symptoms.
  nounced "snips"), where two alternate bases
  occur at one position (Taillon-Miller et al 1998).     Finally, the response phenotype must not only
  Comparison of any two genomes reveals around           be limited to psychopathology ratings but also
  one SNP per kilobase, i.e. across three billion        needs to include functional assessments such as
  base pairs of human DNA statistically three            repeated neuroendocrine testing of the hypotha-
  million SNPs occur. However, the frequency of          lamic-pituitary adrenocortical system (Holsboer
  SNPs varies between genomic regions and                2000) and cognitive functions, just to name a
  between coding and noncoding regions, and the          few options. The ultimate goal of the pharma-
  extent of nucleotide diversity ranges from             cogenomic strategy is to match an individual
  0.0003 to 0.05 resulting in a range of 3-50 SNPs       patient's genotype with an individual drug direc-
  per 10 kilobases when two chromosomes are              ted against the proteins that are derived from
  compared (Chakravarti 1999).                           genes containing one or more functionally rele-
                                                         vant SNPs. These can be located in the promoter
  Hundreds of thousands of polymorphisms can             regions, as well as in exonic or intronic regions
  now be identified and precisely ordered in a           of a gene. These SNPs can thus alter transcrip-
  high-density SNP map (Roses 2000; The Inter-           tional regulation, mRNA transport, translation
  national SNP Map Working Group 2001). The              or degradation, or lead to amino acid substitu-
  SNP Consortium, an international collaboration         tion. They may also affect mRNA splicing as well
  of academic centres, pharmaceutical companies          as phenotype effects through differences in
  and a private foundation, has recently published       mRNA structure (Shen et al 1999). The entirety
  a SNP map of the human genome containing               of these changes opens ample opportunities for
  1.42 million variants (Reich et al 2001). Such         novel drug targets, for prediction of drug
  SNP maps will be particularly useful for iden-         response and for identification early on in the
  tifying genes associated with polygenic disease,       development process of compounds destined for
  where each gene variant only adds a small              failure due to toxicity or poor efficacy.
  increase in relative risk; thus a certain number of
  variants must be coincidently present to pass the      As outlined above, current pharmacotherapy of
  threshold to cause disease. Due to poor pheno-         depression marks one of the greatest successes of
  type definition of patients with affective disorder    medicine, despite the fact that the mechanism of
  and the absence of meaningful candidate genes,         action through which they achieve remediation
  studies that attempt to identify genes and their       is unknown, as is the pathogenesis of depression.
  variants associated with a certain clinical feature    In the absence of this information it does not
  have inherent methodological problems. These           come as a surprise that pharmacogenomic
  can only be overcome by genome-wide screens            studies of affective disorders are rare. As listed in
  and rigid clinical phenotyping of affected indi-       Table 2, six out of seven such studies embarked
  viduals that involves consequent databasing of         on genes involved in serotonergic neurotrans-
  clinical manifestations.                               mission, believed to be a key mechanism in
                                                         causality and drug treatment of depression
  In contrast to the genetic studies of causality, the   (Lesch and Heils 2000). The serotonin trans-
  pharmacogenomic strategy could provide                 porter is encoded by a single gene (17q11.2 – 12),
  success in the much nearer future. Pharmaco-           which is controlled by a promotor for which a
  genomics use high-density SNP maps to correlate        functional polymorphism has been reported.


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   A   Patient I


                                   restriction       colorcoding       95° C




       Patient II

                                      SNP




       blood sample     genomic DNA          restriction =                     denaturation   Microarray spotted with oligodeoxy           SNP on a chip
                                             gene fragment                                    nucleotides complementary to gene
                                                                                              fragments
                             DNA
                      critical sequence
                                                                                                                               SNPs predictive
   B                                                 Drug Responders
                                                                                                                               of drug response

                                                     Drug Non responders                                                       SNPs predictive
                                                                                                                               of drug non response



  Figure 4
  Genotyping as a fundament of customized antidepressant therapy:
  Generation of single nucleotide polymorphism (SNP) maps of individual patients may lead to individualized pharmacotherapy.
  A: Patient I has a different SNP than Patient II, as reflected by different colouring of spots on cDNA microarrays.
  B: Certain constellations of SNPs in critical areas of the DNA may predict whether a patient will respond to a certain pharmacological
  mechanism or not.


                                                                                Table 2
  One of the two variants that were initially iden-
  tified contains an insertion (long variant) and                               Pharmacogenomic studies
  the other a base-pair deletion (short variant). In
  an in vitro assay the basal transcriptional activity                          Candidate gene          Finding                         Reference
  of the long variant was more than twofold
  higher than that of the short variant.                                        Serotonin-transporter   l-allel favourably associated   Smeraldi et al 1998
                                                                                promoter                with response to fluvoxamine
  This difference prompted clinical studies from                                Serotonin-transporter   l-allel favourably associated   Zanardi et al 2000
  which preliminary evidence emerged that those                                 promoter                with response to paroxetine
  patients who have the long variant of the sero-                               Serotonin-transporter   ll-allel predicted faster       Pollock et al 2000
  tonin transporter gene promoter (presumably                                   promoter                response to paroxetine in
  expressing higher quantities of the transporter)                                                      elderly patients
  respond more favourably to antidepressants that                               Serotonin-transporter   ll-genotype in nitron 2 or      Kim et al 2000
  selectively block this transporter function. Thus,                            promoter                S/S-genotype in promoter
  fluvoxamine and paroxetine, both relatively                                                           region associated with better
  selective serotonin reuptake inhibitors (SSRI),                                                       response to SSRS
  were found to be more effective among patients                                Serotonin receptor      No association of genotype      Serretti et al 2000
  genotyped to contain the long variant of the                                  subtype (1A, 2A, 2C)    with lithium response
  gene promoter. The situation is now even more                                 Tryptophan              TPH gene variants tend to       Serretti et al 1999
  complex as 14 allels for the serotonin transporter                            hydroxylase (TPH)       predict lithium response
  gene promoter have been identified so far. In                                 gene polymorphism
  addition, a 381 base-pair insert between the                                  G-Protein ß3-gene       T/T-genotype associated with Zill et al 2000
  polymorphic promoter sequence and the tran-                                   variant C 825 T         favourable antidepressant
  scription start site was found (Flattem and                                                           response
  Blakely 2000). One example of a polymorphic
  gene coding for a protein that functions beyond
  cell membrane receptors is the one reported by
  Zill et al (2000), who identified a G-protein ß3-                             Despite these promises, the future of pharma-
  gene variant that was associated with favourable                              cogenomics will see a radical departure from the
  antidepressant drug response.                                                 "one-gene-at-a-time"-approach, which will be


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  replaced by results from unbiased strategies.          drugable targets. It has been estimated that the
  Using large automated genotyping facilities,           human organism expresses at minimum some
  patient populations will be separated into             five to 10 thousand potential drug targets. Thus,
  subgroups within what used to be considered a          during the next few years we will see a once-only
  single disease. A major focus of the SNP strategy      opportunity to identify each of these targets,
  will lead to gene variants as markers for defining     which may multiply today's number of targets
  populations exhibiting a given clinical pheno-         10-20 fold.
  type. Specifically, a cohort of depressed patients
  indistinguishable according to traditional classi-     Whatever the exact figure of additional drug
  fication algorithms such as the International          targets might be, it is without doubt that there is
  Classification of Disease (ICD-10) or severity         much room for many additional proteins to be
  according to the Hamilton Depression Rating            mimicked or blocked by small molecules. Tech-
  Scale (HDRS) scores may be subclassified using a       niques exploiting these opportunities for brain
  set of SNPs. The patient's genotype then deter-        diseases, and more specifically for affective
  mines to which specific drug action the patient        disorders, encompass expression-profiling stu-
  might respond most favourably. This line of            dies of as many genes as possible that are expres-
  thinking includes the departure of today's "one-       sed in brain tissue following administration of
  size-fits-all" drugs, which are so unspecific that     current antidepressants. Such studies ultimately
  they are likely to hit the pathology of each           need to be unbiased regarding both candidate
  individual case. The down-side of today’s "wide-       genes and the specific brain area involved.
  spectrum"-antidepressants is their side-effect         Today, techniques are available which combine
  profile, protracted time to onset of action and        laser capture microdissection with appropriate
  the sizeable portion of non-response, which hits       amplification techniques scaling up minute RNA
  one out of five patients. In summary, these            quantities derived from a small number of
  adverse effects are one major reason for               neurons (Luo et al 1999). As mentioned above
  undertreatment of depression and possibly also         not RNAs but the manifold proteins to which
  the uncritical embracement of herbals and              they are translated regulate cellular processes
  alternative medicines.                                 and are potential drug targets. Proteomics is the
                                                         study of the whole spectrum of proteins ex-
  As illustrated in Figure 4, I expect that the SNP      pressed by the genome, including their function.
  maps can be deployed as a binary molecular sig-        In comparison to genomics, proteomics is
  nature associated with enhanced disease suscep-        burdened with more complexities. A single gene
  tibility or predictive value for treatment outcome     can give rise to many different proteins and the
  and long-term prognosis. In addition, another          function or dysfunction of these proteins and
  near-term opportunity for SNP genotyping is            the pathways they participate in are often
  optimization of clinical trials through patient        dependent on posttranslational modifications
  stratification according to genotype and accor-        and not encoded in the genome. Another closely
  ding to the responder/nonresponder status for a        linked complexity is that the proteome is subject
  given drug. Once novel drugs directed to much          to acute or long-term changes secondary to
  more specific targets become available, geno-          external factors. To put it more bluntly, the pro-
  typing of patients will become an essential            teome changes following a major stressful life
  routine requirement prior to drug prescription.        event, while the genome does not. Adminis-
                                                         tration of an antidepressant drug changes
  Pharmacoproteomics of affective                        expression activity of many genes and produces
  disorders                                              functional changes in nerve cells due to changes
                                                         in their protein composition.
  Almost all successful drugs either target or are
  proteins which constitute the final form of gene       Pharmacoproteomics comprises the study of
  expression. Importantly, the genetic sequence          drug-induced changes upon the entirety of
  cannot effectively predict posttranscriptional         proteins, their nature and function, within
  and posttranslational effects, and messenger           single nerve cells and neuronal circuitries. Pro-
  RNAs (transcripts of genomic DNA that directly         tein analysis is particularly challenged to keep
  encode proteins) can be assembled in many              pace with the high-throughput techniques used
  different ways (Eisenberg et al 2000). Further,        in genomics. Classical techniques separate
  expressed proteins are typically modified in a         proteins using two-dimensional (2-D) gel electro-
  variety of ways, such as by phosphorylation or         phoresis. In this technique, proteins are sepa-
  glycosylation; these biochemical steps are             rated in one dimension based on charge and in a
  necessary to allow for specific cellular function.     second dimension based on molecular size. By
  Considering the entirety of possible posttrans-        comparing the patterns of protein spots between
  lational modifications, over 750 000 potentially       various clinical conditions (patient versus
  important proteins derived from 30-40 thousand         healthy control, or patient with drug versus pa-
  genes seems to be a realistic estimate. In the light   tient without drug treatment), those proteins
  of these numbers, the current 500 or so targets of     that are characteristic for the disease or the effect
  current drugs in the modern pharmacopeia are           of a given drug can be identified. Specifically, a
  certainly only a minor fraction of potentially         depressed patient who favourably responds to a


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  certain class of drugs, e.g. an SSRI, might differ in                   mens of patients with depression are mass
  his or her protein expression profile changes                           analysed following a proteolytic digest at 2-D-
  when compared to a nonresponder. Establish-                             electrophoresis and the database compared to
  ment of a database elucidating this research issue                      that obtained from the same patients following
  is the focus of the MARS project at the Max                             successful treatment. Comparison of the emer-
  Planck Institute of Psychiatry in Munich.                               ging data may provide a clue to proteins that are
                                                                          causally related to the disease process and
  The current lack of reliable high-throughput                            additionally to proteins that are modified by
  technology is a major impediment for proteome                           drug action. Novel drug targets may be derived
  analysis. The 2D-gel-electrophoresis needs to be                        from such studies.
  linked to capillary liquid chromatography/elec-
  trospray ion trap mass spectrometry to identify                         Several attempts are underway to replace current
  proteins whose expression level differs across the                      2-D-gels by chip-based technologies. One of
  two clinical conditions. One breakthrough tech-                         these techniques attempts to overcome the
  nology is the matrix-assisted laser desorb-                             laborious and costly 2-D-gel-electrophoresis by
  tion/ionisation time-of-flight mass spectrometry                        using ProteinChip® Arrays, which allow pro-
  MALDI-TOF-MS (or short, MALDI) analysis of                              cessing of blood, CSF or tissue extract sample
  proteins. At the core of this technique is a                            directly upon the chip. The array surface can be
  "matrix" consisting of a crystal-like structure of                      a chemical surface with broad specificity so that
  weak organic acids into which digested proteins                         it binds whole classes of proteins, or more
  are embedded. The matrix, responsible for ioni-                         specific surfaces, only binding proteins with
  zation, facilitates desorbtion and prevents the                         certain properties for a preselection. Following a
  protein from decomposition when hit by a laser                          series of washes to remove unbound proteins
  beam. Hence, a matrix has to be chosen that                             and interfering substances, the chips are inserted
  strongly absorbs the energy of the laser beam at                        into a reader, consisting of a surface-enhanced
  a wavelength where the proteins exhibit only                            laser desorption/ionisation (SELDI)-MS techno-
  weak absorbtion. Each protein molecule is                               logy. This technique is based on similar prin-
  charged through ionisation and once desorbed it                         ciples as MALDI. The ProteinChip® – SELDI
  enters an electric field resulting in acceleration                      technique promises to identify disease-related
  (Figure 5). Heavier molecules fly less quickly                          biomarkers and has been successful in gene-
  (time-of-flight) through a certain field-free drift                     rating protein marker profiles for prostate cancer.
  distance, which at its end detects the protein                          Studies will reveal whether "protein-fingerprints"
  ions according to their mass in ascending order.                        from depressed patients will become available
  Before this MALDI technique can be employed,                            that predict response to drug treatment. Clearly,
  however, the proteins need to be separated by                           such expectations are much more challenging
  two-dimensional (2-D)-gel-electrophoresis. In                           than fingerprinting clinical conditions such as
  combination with 2-D-gel-electrophoresis and                            advanced cancer. High quality targets are the key
  fast-growing protein databases, MALDI allows                            to more specific and safer drugs, and thereby to
  identification of the entire protein content of a                       better tools for practising clinicians. Proteins
  tissue or a cell preparation at a given time point.                     discovered by the above techniques must be
  As an example, cerebrospinal fluid (CSF) speci-                         physiologically relevant, and tractable to drug


          SpectroCHIPs                Laser                 Flight Tube              Detector




  MATRIX ASSISTED LASER DESORPTION / IONIZATION – TIME OF FLIGHT

  Figure 5
  MALDI-TOF mass spectrometry
  Proteins are analysed by combining chip technology with mass spectrometry. This allows identification of which proteins are altered in their
  function due to genetic and/or external factors.


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  development, that is, they must possess poten-        by hypothesis-driven studies where candidate
  tial binding sites for small molecules that will      genes are assessed directly in as many patients as
  modulate (i.e. antagonize) their function. One        possible. This will require concerted efforts,
  important aspect is that the three-dimensional        where (1) patients are clinically and functionally
  structure and function of a protein cannot be         phenotyped and monitored during clinical
  predicted simply on the basis of its primary          course and after remission and (2) large
  amino acid sequence. Thus, considerations on          interoperable databases of many clinical centres
  structure-activity relationships need recognition     are created that allow combination of clinical
  of protein folding. Further, proteins act in con-     information with that emerging from geno-
  cert, therefore another important field in            typing centres.
  pharmacoproteomics is the interaction of pro-
  teins. Today, a highly efficient technique exists     In depression these efforts may possibly generate
  which allows the survey of millions of different      the most unwieldy datasets in medicine and the
  protein-protein interactions in yeast and the         pay-off of SNP maps will not come anytime
  construction of geographical protein-protein          soon. Thus, the expectation that when afflicted
  interaction maps. It is beyond the scope of this      by depression we simply need to hand in our
  review to describe this method (called yeast-two-     personal genome-wide SNP map to get a tailor-
  hybrid) in detail, but it needs to be stressed here   made drug that guarantees swift remediation is
  that once proteins are identified as markers of       perhaps not going to become reality soon, but is
  antidepressant response, the available techno-        rather a long-term goal. However, the combined
  logies allow identification of specific protein       exploitation of phenotyping (phenome), genoty-
  domains that interact with the protein of             ping (genome) and protein analysis (proteome)
  interest. Such knowledge is a good start for anti-    will provide rich information that leaves enough
  depressant modelling studies, ultimately leading      room for new drugs that are applicable also to
  to products that are more specific, safer and         larger populations of affected patients (Figure 6).
  induce a faster onset of action than the current      The hypothesis-driven approach where clinical
  antidepressants.                                      findings on stress hormone dysregulation were
                                                        translated into basic protocols ultimately resul-
  A glimpse to the future – blockbusters or             ting in CRHR1 receptor antagonists is perhaps a
  customized antidepressants?                           first step into this direction. Assessing all genes
                                                        directly or indirectly involved in glucocorticoid
  While entering the postgenomic era anti-              and CRH receptor signalling in as many patients
  depressant research faces exciting new oppor-         as possible may help to identify patients who are
  tunities. The currently available drugs were          potential responders to drugs targeting this neu-
  originally designed and marketed to work in as        roendocrine system. There are many other
  many patients as possible, comparable to wide-        possible sets of candidate genes to be identified
  spectrum antibiotics. The new era, however, will      using high-throughput technology, such as
  no longer define patients (and indications for        cDNA microarrays that can be explored accor-
  drugs) according to traditional diagnostic algo-      ding to their potential as drug targets. I expect
  rithms. Instead, patients will be additionally        that in the near future genotyping and pheno-
  characterized according to functional (e.g.           typing of patients will assist the prescription of
  neuroendocrine, neuropsychological, sleep-EEG,        the right drug to the right patient, minimizing
  neuroimaging, proteome) and genetic (SNP              the risk of adverse effects, avoiding refractoriness
  maps) assessments. In the near future a pro-          and possibly shortening the time to onset of
  teomic fingerprint will be a relay between            action. In the long-term perspective, however, a
  genotype and the current phenotypic battery.
  The decision-making process for the clinicians
  about which drug may work best for an indi-           Current Diagnostic Schemes                 Future Diagnostic Schemes
  vidual patient will be governed by successful
                                                                                                         Psychopathology
  databasing of all the information collected from                                                       Demography
                                                         ICD - 10, DSM IV +          Behavioural
  patients. It needs to be recognized that random                                                        Family History
                                                                                                         Life History
  collections of single-base variations in DNA will
  not necessarily yield a short cut to identifying                                                       Neuroendocrinology
                                                                                                         Neuropsychology
  patients who will respond to a certain chemical                                    Functional          Neuroimaging
                                                         Phenotype                                       Proteome
  compound. Current and future drugs will target
  proteins, and only a minor fraction of SNPs pro-       Genotype                                        Single Nucleotide
                                                                                      Genetic            Polymorphisms (SNP)
  duces protein alterations that ultimately account                                                      Linkage
  for the clinical phenotype. In fact among those                                                        Candidate Genes
  SNPs that fall into the estimated 5-7% of the
  coding area of the genome, most behave in a           Figure 6
  "synonymous" or silent way, coding for the same       Current diagnostic schemes need to be replaced by appropriate
  protein that an alternate SNP codes for.              phenotyping algorithms.
  "Nonsynonymous" coding SNPs (cSNPs) are very          Meaningful phenotype/genotype correlations require extension of
                                                        patient characterization to the functional level including, for
  scarce, which is why current research needs to        example, hormone regulation, neuropsychology, brain imaging
  complement its activities for discovering cSNPs       and spectroscopy, and the proteome.


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  stepwise fragmentation of the market will take                       coronary artery disease. Am J Psychiatry 155: 4-11.
  place. The closer we get to translating a diseased
                                                                       Hasenöhrl RU, Jentjens O, De Souza S, Tomaz C, Huston JP (1998)
  individual's genetic make-up and phenotype                           Anxiolytic-like action of neurokinin substance P administered sys-
  into a specific pharmacological demand, the                          temically or into the nucleus basalis magnocellularis region. Eur J
  better the drug will act in this particular patient.                 Pharmacol 354: 123-133.
  The same drug, however, will act worse in
                                                                       Holsboer F (1999) The rationale for corticotropin-releasing hor-
  patients with a different genotype/phenotype                         mone receptor (CRH-R) antagonists to treat depression and
  pattern than the traditional "one-size-fits-all" –                   anxiety. J Psychiatr Res 33: 181-214.
  drug. In essence, a biotechnology-driven drug
  discovery can only lead to measurable success                        Holsboer F (2000) The corticosteroid receptor hypothesis of de-
                                                                       pression. Neuropsychopharmacology 23: 477-501.
  when combined with improvements in clinical
  phenotyping of patients. Advances in drug                            International Human Genome Sequencing Consortium (2001)
  development are to be expected in both direc-                        Inititial sequencing and analysis of the human genome. Nature
                                                                       409: 860-921.
  tions, the "blockbusters" being more effective in
  sizeable patient samples meeting specific                            Keck M, Welt T, Wigger A, Renner U, Engelmann M, Holsboer F,
  genotype/phenotype patterns as well as in                            Landgraf R (2001) The anxiolytic effect of the CRH1 receptor
  customized therapies. The latter will have to                        antagonist R121919 depends on innate emotionality in rats. Eur J
                                                                       Neurosci 13: 171-380.
  await the full exploitation of a huge SNP archive,
  containing the entire coding region and                              Kramer MS, Cutler N, Feighner J, Shrivastava R, Carman J, Sramek
  including regulatory sequences of the genome of                      IJ, Reines SA, Snavely D, Wyatt-Knowles E, Hale EJ, et al (1998)
  a very large patient population.                                     Distinct mechanism for antidepressant activity by blockade of
                                                                       central substance P receptors. Science 281: 1640-1645.

  More than 60 years ago Kurt Schneider, a former                      Lancel M, Wigger A, Landgraf R, Müller-Preuss P, Holsboer F (In
  director of the Deutsche Forschungsanstalt für                       Press) The CRHR-R1 antagonist R121919 attenuates stress-eliceted
  Psychiatrie (the predecessor of today's Max                          sleep disturbances in rats, particularly in those with high innate
                                                                       anxiety. J Psychiatr Res.
  Planck Institute of Psychiatry), formulated in his
  book "Psychiatrischer Befund und psychiatrische                      Lesch KP, Heils A (2000) Serotonergic gene transcriptional control
  Diagnose" ("Psychiatric findings and psychiatric                     regions: targets for antidepressant drug development? Int J
                                                                       Neuropsychopharmacol 3: 67-79.
  diagnosis") the provisional nature of psycho-
  pathology and predicted that once a "somatolo-                       Lundberg JM, Hökfelt T (1983) Coexistence of peptides and classi-
  gical" platform for making psychiatric diagnoses                     cal neurotransmitters. Trends Neurosci 6: 325-333.
  is established, psychopathology will play only a
                                                                       Luo L, Salunga RC, Guo H, Bittner A, Joy KC, Galindo JE, Xiao H,
  subordinate role in establishing a diagnosis.                        Rogers KE, Wan JS, Jackson MR, Erlander MG (1999) Gene expres-
  While we are still far away from the identi-                         sion profiles of laser-captured adjacent neuronal subtypes. Nature
  fication of causal factors of depression, psycho-                    5: 117-122.
  pathology remains indispensable. But in the
                                                                       McLean S, Ganong AH, Seeger TF, Bryce DK, Pratt KG, Reynolds LS,
  spirit of Kurt Schneider these clinical descrip-                     Siok CJ, Lowe JA, Heym J (1991) Activity and distribution of binding
  tions need to be complemented by functional                          sites in brain of a nonpeptide substance P (NK1) receptor anta-
  and genomic data that in aggregate will pave the                     gonist. Science 251: 437-439.
  way to antidepressant drugs that are better than
                                                                       Musselman DJ, Evans DL, Nemeroff CB (1998) The relationship of
  the ones we currently have.                                          depression to cardiovascular disease: epidemiology, biology, and
                                                                       treatment. Arch Gen Psychiatry 55: 580-592.

                                                                       Nomura H, Shiosaka S, Tohyama M (1987) Distribution of sub-
                                                                       stance P-like immunoreactive structures in the brain stem of the
                                                                       adult human brain: an immunocytochemical study. Brain Res 404:
  References                                                           365-370.

  Carney RM, Freedland KE, Rich MW, Jaffe AS (1995) Depression as      Nussdorfer GG, Malendowicz LK (1998) Role of tachykinins in the
  a risk factor for cardiac events: a review of possible mechanisms.   regulation of the hypothalamo-pituitary-adrenal axis. Peptides 19:
  Ann Behav Med 17: 142-149.                                           949-968.

  Chakravarti A (1999) Population genetics – making sense out of       Penninx BWJH, Beekman ATF, Honig A, Deeg DJH, Schoevers RA,
  sequence. Nat Genet 21: 56-60.                                       van Eijk JTM, van Tilburg W (2001) Depression and cardiac
                                                                       mortality. Arch Gen Psychiatry 58: 221-227.
  Chawla MK, Gutierrez, GM, Young WS, McMullen NT, Rance NE
  (1997) Localization of neurons expressing substance P and            Pollock BG, Ferrell RE, Mulsant BH, Mazumdar S, Miller M, Sweet
  neurokinin B gene transcripts in the human hypothalamus and          RA, Davis S, Kirschner MA, Houck PR, Stack JA, Reynolds CF, Kupfer
  basal forebrain. J Comp Neurol 384: 429-442.                         DJ (2000) Allelic variation in the serotonin transporter promoter
                                                                       affects onset of paroxetine treatment response in late-life
  Eisenberg D, Marcotte EM, Xenarios I, Yeates TO (2000) Protein       depression. Neuropsychopharmacology 23: 587-590.
  function in the post-genomic era. Nature 405: 823-826.
                                                                       Reich DE, Cargill M, Bolk S, Ireland J, Sabeti PC, Richter DJ, Lavery
  Flattem NL, Blakely RD (2000) Modified structure of the human        T, Kouyoumjian R, Farhadian SF, Ward R, Lander ES (2001) Linkage
  serotonin transporter promoter. Mol Psychiatry 5: 110-115.           disequilibrium in the human genome. Nature 411: 199-204.

  Frasure-Smith N, Lesperance F, Talajic M (1993) Depression follow-   Roses AD (2000) Pharmacogenetics and the practice of medicine.
  ing myocardial infarction: impact on 6-month survival. JAMA 270:     Nature 405: 857-865.
  1819-1825.
                                                                       Rupniak NMJ, Kramer MS (1999) Discovery of the anti-depressant
  Glassman AH, Shapiro PA (1998) Depression and the course of          and anti-emetic efficacy of substance P receptor (NK1) antagonists.


                                                                  176
www.cuwai.com




                                                                                                                                         L
  TIPS 20: 485-490.                                                       depression: the first 20 patients treated. J Psychiatr Res 34: 171-
                                                                          181.
  Schwarze SR, Hruska KA, Dowdy SF (2000) Protein transduction:
  unrestricted delivery into all cells? Trends Cell Biol 10: 290-295.

  Serretti A, Lilli R, Lorenzi C, Gasperini M, Smeraldi E (1999) Tryp-
  tophan hydroxylase gene and response to lithium prophylaxis in
  mood disorders. J Psychiatr Res 33: 371-377.

  Serretti A, Lorenzi C, Lilli R, Smeraldi E (2000) Serotonin receptor
  2A, 2C, 1A genes and response to lithium prophylaxis in mood
  disorders. J Psychiatr Res 34: 89-98.

  Shen LX, Basilion JP, Stanton Jr VP (1999) Single-nucleotide
  polymorphisms can cause different structural folds of mRNA. Proc
  Natl Acad Sci 96: 7871-7876.

  Smeraldi E, Zanardi R, Benedetti F, Dibella D, Perez J, Catalano M
  (1998) Polymorphism within the promoter of the serotonin
  transporter gene and antidepressant efficacy of fluvoxamine. Mol
  Psychiatry 3: 508-511.

  Stenzel-Poore MP, Heinrichs SC, Rivest S, Koob GF, Vale WW (1994)
  Overproduction of corticotropin-releasing factor in transgenic
  mice: A genetic model of anxiogenic behavior. J Neurosci 14:
  2579-2584.

  Stout SC, Owens MJ, Nemeroff CB (1999) Preprotachykinin-A and
  neurokinin 1 receptor mRNA expression are unchanged in rat fore-
  brain after chronic antidepressant administration. Soc Neurosci
  Abstracts 25: 1066.

  Taillon-Miller P, Gu Z, Li Q, Hillier L, Kwok PY (1998) Overlapping
  genomic sequences: a treasure trove of single-nucleotide poly-
  morphisms. Genome Res 8: 748-754.

  Teixeira RM, Santos AR, Ribeiro SJ, Calixto JB, Rae GA, De Lima TC
  (1996) Effects of central administration of tachykinin receptor
  agonists and antagonists on plus-maze behavior in mice. Eur J
  Pharmacol 311: 7-14.

  The International SNP Map Working Group (2001) A map of
  human genome sequence variation containing 1.42 million single
  nucleotide polymorphisms. Nature 409: 928-933.

  Timpl P, Spanagel R, Sillaber I, Kresse A, Reul JMHM, Stalla GK,
  Blanquet V, Steckler T, Holsboer F, Wurst W (1998) Mice lacking a
  functional corticotropin-releasing hormone receptor 1 show
  impaired stress response and reduced anxiety under basal and
  alcohol withdrawal conditions. Nat Genet 19: 162-166.

  Uhr M, Steckler T, Yassouridis A, Holsboer F (2000) Penetration of
  amitriptyline, but not fluoxetine, into brain is enhanced in mice
  with blood-brain barrier deficiency due to mdr1a P-glycoprotein
  gene disruption. Neuropsychopharmacology 22: 380-387.

  Vale W, Spiess J, Rivier C, Rivier J (1981) Characterization of a 41-
  residue ovine hypothalamic peptide that stimulates secretion of
  corticotropin and ß-endorphin. Science 213: 1394-1397.

  Venter JC, Adams MC, Myers EW, Li PW, Mural J, Sutton GG, Smith
  HO, Yandell M, Evans CA, Holt RA, et al (2001) The sequence of the
  human genome. Science 291: 1304-1350.

  Wittchen HU (2000) Depression 2000. Eine bundesweite
  Depressions-Screening-Studie in Allgemeinarztpraxen. Fortschr
  Med Suppl, Sonderheft 1/2000.

  Zanardi R, Benedetti F, Di Bella D, Catalano M, Smeraldi E (2000)
  Efficacy of paroxetine in depression is influenced by a functional
  polymorphism within the promoter of the serotonin transporter
  gene. J Clin Psychopharmacol 20: 105-107.

  Zill P, Baghai TC, Zwanzger P, Schüle C., Minov C, Riedel M,
  Neumeier K, Rupprecht R, Bondy B (2000) Evidence for an
  association between a G-protein ß3-gene variant with depression
  and response to antidepressant treatment. NeuroReport 11: 1893-
  1897.

  Zobel AW, Nickel T, Künzel HE, Ackl N, Sonntag A, Ising M,
  Holsboer F (2000) Effects of the high-affinity corticotropin-
  releasing hormone receptor 1 antagonist R121919 in major


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  Psychopharmacogenetics - a Challenge
  for Pharmacotherapy in Psychiatry
  Brigitta Bondy, Peter Zill
  Department of Psychiatry, Ludwig-Maximilians-University, Munich, Germany

  Summary                                                  Introduction
  Differences in response to treatment or the incidence    The introduction of chlorpromazine in 1952
  of adverse drug effects are quite common in clinical     revolutionised the treatment of psychiatric
  psychopharmacotherapy. Although several factors          disorders. Although several different classes of
  may account for these discrepancies, there is in-        drugs have been developed and applied since
  creasing knowledge that genetic factors play a major     that time, and although the efficacy of many
  role. The aim of pharmacogenetics, a new and             substances is established, large interindividual
  rapidly growing field in research, is to elucidate the   differences in outcome and side effects are quite
  variability in drug response and metabolism due to       common for this group of therapeutics. Thus,
  hereditary differences. According to the hypotheses      also at recommended doses the clinical response
  on the mechanisms of drug action, several mutations      of drugs might range from "good effect" to "no
  in genes coding for neurotransmitter receptors, de-      response" or even "deterioration", with a high
  grading enzymes, transport proteins or enzymes of        incidence of adverse effects, and still today the
  the drug metabolizing system (P-450 isoenzymes)          selection of psychoactive drugs in clinical the-
  have been identified and investigated in psychiatric     rapy relies much more on experience than on
  disorders over the last years. Although some             scientific hypotheses.
  controversy exists among the results, many studies
  are supportive of the hypothesis that psychopharma-      Although these observed patient to patient dif-
  cogenetics will be helpful in predicting an individual   ferences may be caused by many factors such as
  patient´s drug response while minimising the rate of     age, gender, body fat, alcohol intake or nicotine
  side effects.                                            consumption, there is increasing evidence that
                                                           also genetic factors underlie the differences in
  Key words: pharmacogenetics, drug response,              psychopharmacological drug response (Catalano
  treatment, neurotransmitter receptors, metabolizing      1999; Smith and Mendoza 1996). This hypo-
  enzymes.                                                 thesis is further supported by observations of
                                                           similar responses to antidepressant therapy
  Correspondence:                                          among relatives (Franchini et al 1998). Thus, the
  Prof. Dr. Brigitta Bondy                                 concept of pharmacogenetics as originally de-
  Department of Psychiatry                                 fined by Vogel in 1959, i.e. heritable differences
  Ludwig-Maximilians-University                            in metabolism and activity of exogenous agents,
  Nussbaumstraße 7                                         might also help to unravel variability in drug
  80336 Munich                                             response and metabolism due to hereditary
  Germany                                                  differences.
  Tel: +49 89 5160 2737
  Fax: +49 89 5160 4741                                    The majority of genetic polymorphisms found to
  E-mail: bb@psy.med.uni-muenchen.de                       date are in drug metabolizing enzymes, neuro-
                                                           transmitter receptors and transport proteins.
  Acknowledgement                                          These genetic variants either have no effect, or
  The authors are supported by the German Federal          result in a change in the rate of metabolism and
  Research Ministry within the promotional emphasis        in altered protein binding and/or function
  "Competence Nets in Medicine".                           (Wieczorek and Tsongalis 2001). Accordingly,
                                                           most studies focus on the cytochrome P-450
                                                           isoenzymes, neurotransmitter receptors and
                                                           selective transporters, following the hypotheses
                                                           of pathophysiological and drug action mecha-
                                                           nisms. But also newer concepts of a drug´s site of
                                                           action, such as the signal transduction cascade or
                                                           the neuropeptides, are gaining importance in
                                                           this field of research. This review outlines some
                                                           important and promising results of the rapidly
                                                           growing field of psychopharmacogenetics

                                                           Drug metabolizing enzymes

                                                           Metabolizing enzymes were recognised early on
                                                           as a major source of pharmacokinetic variability


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  (interindividual variation in elimination rates,      and related them to variants of the CYP2D6
  steady state concentrations and biotransfor-          genes. All patients were treated with haloperidol
  mation) within and between patients. The              at 3 to 40 mg/day (mean 11.3 mg), and steady
  lipophilic psychotropic drugs are extensively         state was reached after seven days of treatment
  metabolized by isoenzymes of the cytochrom P-         (haloperidol: 7.6±5.9 ng/ml; reduced haloperidol
  450 (CYP) system. More than 30 isoforms are           5.8±3.4 ng/ml). According to literature, 9.55%
  known today, but only a few of them have clini-       were carriers of one allele 4 (CYP2D6*4, the poor
  cal significance in psychiatry as they are invol-     metabolizing variant). In those patients, the
  ved in a vast number of biotransformations and        plasma concentrations of haloperidol and
  exhibit significant genetic polymorphisms, such       reduced haloperidol were significantly increased
  as the CYP3A, CYP2D6, CYP2C19 and CYP2C9              (p=0.02, T-test) compared to patients with the
  (Wieczorek and Tsongalis 2001). Variants in           CYP2D6 wild-type. Furthermore, we observed
  these genes can lead to three possible pheno-         early dyskinesia in nine out of 10 carriers of
  types: poor (PM), normal (NM) and extensive           allele 4, whereas 24% of the homozygotes of the
  (EM) metabolizers. PM lack an active form of the      wild-type had no extrapyramidal symptoms.
  expressed enzyme due to an inactivating poly-         Similarly, carriers of allele 4 had a delayed
  morphism, NM have at least one copy of an             response to haloperidol treatment (differences in
  active gene, and EM contain duplicated or am-         PANSS, significant after two weeks of treatment,
  plified gene copies.                                  p=0.01). Although these results have to be
                                                        confirmed, they could be suggestive of a direct
  The most extensively screened P-450 isoenzyme         relationship between the CYP2D6 poor meta-
  in psychiatric disorders is the CYP2D6. Several       bolizing variant (allele 4) and haloperidol plasma
  metabolically active polymorphisms are known,         concentration. The fact that extrapyramidal
  as is the existence of considerable ethnic diffe-     symptoms seem to occur more frequently in
  rences of these variants (Arranz et al 2001b).        poor metabolizers might be explained by an
  About 7% of Caucasians, 1 % of Asians and 7-8%        increased formation of toxic metabolites via the
  of Africans are classified as poor metabolizers,      CYP3A4 system (Weber et al In Preparation).
  which means that they might exhibit increased
  concentrations of metabolized drugs at conven-        Genotyping of metabolizing enzymes might
  tional doses (Cichon et al 2000). On the other        have clinical implications, as it is known that
  hand, EM and ultrarapid metabolizers often do         combinations of drugs that are metabolized by
  not reach therapeutic doses and may require           CYP2D6 may lead to dangerous pharmacokinetic
  higher intake of drugs to achieve therapeutic         interactions, particularly in PMs. Furthermore,
  response.                                             since some antipsychotics are competitive inhi-
                                                        bitors of CYP2D6-mediated oxygenation, even
  Although many clinical investigations are             EM might become apparent PM when these
  carried out parallel to the search for novel          drugs are given in combination (Alfaro et al
  mutations, the results are still not conclusive. As   1999). Thus, the knowledge of an individual's
  far as neuroleptics are concerned, a relationship     metabolic rates will help to adjust therapeutic
  has been shown between extensive/poor me-             doses or combinations accordingly.
  tabolizers and the plasma concentration in
  healthy volunteers after one single dose (Fang        Neurotransmitter receptors
  and Gorrod 1999), thus at least partly explaining     and transporters
  the variation in drug clearance. Among psycho-
  tic patients who had experienced severe auto-         Genetic variants in neurotransmitter receptors or
  nomic side effects within the first days of           in selective transporters might also be a potential
  treatment, an overrepresentation of poor meta-        source of interindividual variation in drug res-
  bolizers was found (Spina et al 1992). On the         ponse. Polymorphisms in the DNA sequence of
  other hand, it is not clear whether the develop-      these target proteins might alter the rector
  ment of tardive dyskinesia is associated with a       structure, their function and the level of their
  reduced metabolizing capacity of CYP2D6               expression, thus exerting a direct effect on the
  (Kapitany et al 1998; Andreasen et al 1997).          mechanisms triggered by the drug. Within the
                                                        last years several candidate genes have been
  Haloperidol is one of the most commonly used          investigated in relation to drug response, mainly
  drugs in psychosis treatment. It is metabolized       those encoding for proteins of the dopaminergic
  by reduction to reduced haloperidol. Although         and the serotonergic pathway, since both sys-
  the metabolism via CYP2D6 is only a minor             tems are suggested to play major roles in
  pathway for haloperidol, the plasma half-life of      endogenous psychoses and in their treatment.
  both haloperidol and reduced haloperidol was
  found to be longer in poor metabolizers than in       Table 1 summarises several studies in this field.
  extensive metabolizers.                               Concerning the serotonin (5-HT) receptors,
                                                        especially the 5-HT2A type as the main target of
  We evaluated the plasma concentrations of halo-       atypical neuroleptics, an association with the
  peridol and reduced haloperidol in 91 schizo-         response to clozapine was reported in several
  phrenic patients (according to DSM-IV criteria)       investigations, but negative results were reported


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  as well (Arranz et al 2001a). Overall, a meta-                                schizophrenia, although the presence of at least
  analysis showed that a silent polymorphism                                    one allele 1 of the Taq I polymorphism results in
  (T → C exchange at position 102) and a struc-                                 lower DRD2 receptor expression, which might
  tural His452Tyr substitution in the 5-HT2A gene                               alter the susceptibility to neuroleptic drugs
  influence the response to clozapine (Arranz et al                             (Thompson et al 1997). Recently it was shown
  1998). Interestingly, also in depressive patients                             that patients with one or two alleles 1 of this
  we were able to identify a relationship between                               DRD2 variant showed a better early therapeutic
  the 5-HT2A-102C allele and the response to                                    response to nemanopride than carriers of allele 2
  antidepressant medication (Minov et al 2001).                                 (Suzuki et al 2000). In our own study with schi-
  These results suggest that polymorphisms in the                               zophrenic patients being treated with haloperi-
  5-HT2A receptor gene might affect the response                                dol, we could replicate this finding since allele 1
  to treatment with both neuroleptics and                                       carriers showed a better improvement of positive
  antidepressants.                                                              symptoms of schizophrenia, but not of negative
                                                                                ones (Schäfer et al 2001). These results support
                                                                                the hypothesis that a functionally active variant
  Table 1                                                                       in the DRD2 may have some impact on indivi-
  Polymorphisms in neurotransmitter receptor and transporter genes, and         dual response to treatment with neuroleptics,
  response to treatment                                                         which have dopamine receptors as the main
                                                                                target of drug action.
  Gene     Polymorphism         Clinical Effect       References
                                                                                Signal transduction as a target for drug
  5-HT2A T102C (silent)         Clozapine response    (Arranz et al 1995)       action
                                non-replication       (Masellis et al 1998)
                                response to           (Minov et al 2001)        Clinical, pharmacological and animal studies
                                antidepressants                                 have given increasing evidence that disturbances
                                                                                in molecular signal transduction mechanisms
  5-HT2C Cys23Ser             Clozapine response      (Sodhi et al 1995)        are involved in the pathophysiology of psy-
         (receptor – binding) non-replication         (Malhotra et al 1996)     choses and in the mechanism of psychotropic
                                                                                drug action (Rasenick et al 1996). Especially the
  DRD3     Ser9Gly              Clozapine responses (Scharfetter et al          G-proteins (guanine nucleotide binding pro-
           (receptor – binding) non-replication      1999)                      teins) have a key function, since they represent
                                                    (Malhotra et al 1998)       essential regulatory components in transmem-
                                                                                brane coupling of neurotransmitter receptors
  DRD2     Taq 1                Nemonaprid response (Suzuki et al 2000)         with internal second messenger systems, such as
           (receptor – binding) Haloperidol response (Schäfer et al 2001)       the adenylylcyclase and the phosphoinositide
                                                                                cycle, and thus initiate the cellular responses (Fi-
  5-HTT    5-HTTLPR             Fluvoxamine           (Smeraldi et al           gure 1). Increase in intracellular calcium ions as
           (transcription       response              1998)                     an early event of the signal transduction cascade,
            activity)           Paroxetine response   (Pollock et al 2000)      the activation of several protein kinases and the
                                                                                regulation of transcription factors are important
  5-HT2A = serotonin-2A-receptor; 5-HT2C = serotonin-2C-receptor; DRD3 =        compartments of the adaptive changes during
  dopamine D3-receptor; DRD2 = dopamine-D2-receptor; 5-HTT = serotonin-         psychopharmacotherapy (Chen et al 1999).
  transporter (5-HTTLPR)
                                                                                G-proteins are composed of three subunits and
                                                                                dissociate after receptor activation into the Gα
  Among dopamine receptors, the DRD3 receptor                                   and the Gβγ units. The free guanosine tri-
  subtype gained much interest because of its                                   phosphate (GTP)-bound α subunit modulates
  localisation within limbic structures and its                                 specific effectors, but recent evidence suggests
  affinity for classical and atypical neuroleptics.                             that also the β and γ subunits might contribute
  The Ser9Gly polymorphism of the DRD3 was not                                  to the specificity of the interaction of the G-pro-
  only associated with schizophrenia but also with                              teins with receptors and effectors. The majority
  its possible involvement in the action of classical                           of the investigations have been carried out with
  neuroleptics and clozapine (Shaikh et al 1996;                                the Gα subunit, but at present there is no
  Malhotra et al 1998; Scharfetter et al 1999).                                 evidence that the alteration in levels or function
  Moreover, an association of this Ser9Gly poly-                                of Gα is caused by mutations in the Gas gene
  morphism with the development of tardive dys-                                 itself (Ram et al 1997).
  kinesia was shown, suggesting a protective in-
  fluence of the Ser9 allele against developing this                            We have investigated a functional polymor-
  disabling adverse effect (Steen et al 1997; Basile                            phism in the β3 subunit of the G-protein
  et al 1999; Segman et al 1999). However, this                                 (C825T) that was related to increased ion flux,
  could not be replicated by others (Rietschel et al                            hypertension and obesity in numerous inves-
  1996).                                                                        tigations (Siffert 1998). In our sample of patients
                                                                                with affective psychoses (major depression and
  So far, the DRD2 receptor has not been the focus                              bipolar disorder), we did not only find a signifi-
  of much attention in pharmacogenetic studies of                               cantly increased frequency of allele 825T in both


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  groups of patients, but also an association of                                            ting with synthesis and production of neuro-
  825T homozygosity with a faster response to                                               active steroids. Because of the repeatedly dis-
  treatment. This might be explained by increased                                           cussed antidepressive action of SP antagonists
  signal transduction and more rapidly occurring                                            (Kramer et al 1998), and the decrease of cerebral
  adaptive changes within the signal transduction                                           SP content after treatment with monoamine-
  cascade (Zill et al 2000).                                                                uptake inhibitors (Shirayama et al 1996), the in-
                                                                                            fluence of SP and the regulation of this neuro-
  There is abundant evidence that the phospha-                                              peptide via the ACE concentration are becoming
  tidyl inositol system (PI) is involved in the me-                                         interesting goals for studies on pathophysiology
  chanism of action of lithium ions (Belmaker et al                                         and the treatment of affective disorders. About
  1996). Inhibition of the enzyme inositol mono-                                            50% of the interindividual variability of the ACE
  phosphatase, and altered production of the                                                concentration is determined by an inser-
  second messengers diacylglycerol (DAG) and                                                tion/deletion (I/D) polymorphism in the ACE
  inositol triphosphatase (IP3) via stimulation of                                          gene. The D-allele was associated with higher
  phospholipase C (PLC), are fairly well esta-                                              ACE levels and higher neuropeptide degradation
  blished as one of the initiating effects of lithium                                       capabilities (Rigat et al 1990). Moreover, an asso-
  (Figure 1). This key position of PLC makes the                                            ciation between the D/D genotype and affective
  genes coding for the different PLC isoenzymes                                             psychoses was found in Japanese patients
  interesting candidates for pharmacogenetic                                                (Arinami et al 1996). Although we could not
  investigations. A (CA)n repeat polymorphism in                                            replicate these findings, we have observed a di-
  the gene coding for the PLC-γ1 isoenzyme was                                              vergent clinical outcome in patients with
  associated with bipolar disorder. According to                                            different genotypes, as carriers of allele D had a
  our own results, the presence of long alleles                                             significantly earlier response to treatment and
  might be a predisposing factor for developing                                             shorter duration of hospitalisation than the I/I
  hand tremor (Bondy et al Submitted).                                                      genotypes (Baghai et al 2001). Thus the D-allele
                                                                                            might positively influence the onset of thera-
                                                                                            peutic efficacy. On the other hand, patients who
        Receptor                          Receptor                   Receptor               are homozygous for allele I might be responders
                      β              β                         Gq                           to treatment with substance P antagonists.
                          γ     γ                          β
   G-Proteins   Giα                      Gsα           γ
                                                                    PLC
                          Adenylyl                                                          Future perspectives
                          cyclase                                          PIP2
   First Messengers
                                                                                            Although many investigations have shown that
                                                                                            genetic variations in target proteins influence
   Second Messengers: cAMP                             DAG          IP3           Ca
                                                                                       2+
                                                                                            their interaction with psychotropic drugs, the
                                                                                            results are still not conclusive and far from the
                                                                                            original concept of tailoring the drug regimen to
                          Protein Kinases: PKA, PKC, CAMK                                   an individual's predisposition and predicting a
            (Regulation of substrate proteins, e.g. receptors, ion channels,                patient's response to therapeutic agents. How-
                     cyto-skeletal proteins, transcription factors)                         ever, taking into account that many other factors
                                                                                            besides allelic variants may contribute to the
                                                                                            final phenotype of "responder" or "non-respon-
                                                                                            der", we cannot assume a one-to-one relation-
                 Short- and long-term regulation of neuronal function                       ship between genotype and phenotype. More-
                                                                                            over, we have to assume that, similar to the
                                                                                            pathophysiological mechanisms of complex
  Figure 1                                                                                  psychiatric disorders, in drug response different
  The signal transduction cascade as target for drug action
  Activation of G-proteins via neurotransmitter–receptor coupling                           genes also interact and modulate each other,
  leads to generation of various second messengers (e.g. Ca2+, cyclic                       together with environmental factors. Never-
  adenosin monophosphat = cAMP; diacylglycerol = DAG; inositol                              theless, the field of pharmacogenetics is expan-
  triphosphate =IP3) via the effectors (= first messengers). The se-                        ding rapidly and the elucidation of the disease
  cond messengers influence the second messenger-dependent
  protein kinases, which regulate substrate proteins, and finally lead                      processes through genomics, the identification
  to short- and long-term adaptive mechanisms in cellular function.                         of novel drug targets and the subtyping of
                                                                                            patient populations are ambitious methods that
                                                                                            may help us to individualise pharmacological
  Angiotensin-converting-enzyme                                                             therapy.

  The angiotensin-converting-enzyme (ACE) is not
  only involved in blood pressure regulation but
  also highly expressed within the central nervous
  system, where its primary function comprises                                              References
  degradation of neuropeptides including brady-
                                                                                            Alfaro CL, Lam YW, Simpson J, Ereshefsky L (1999) CYP2D6 status
  kinin and substance P (SP). ACE is further sup-                                           of extensive metabolizers after multiple-dose fluoxetine,
  posed to modulate the regulation of the hypo-                                             fluvoxamine, paroxetine, or sertraline. J Clin Psychopharmacol 19:
  thalamic-pituitary-adrenal axis, thereby interac-                                         155-163.


                                                                                       181
www.cuwai.com


                                        L
   REVIEW/MINI-REVIEW

  Andreasen OA, MacEwan T, Gulbrandsen AK, McCreadie RG, Steen            Malhotra AK, Goldman D, Mazzanti C, Clifton A, Breier A, Pickar D
  VM (1997) Non-functional CYP2D6 alleles and risk for neuroleptic-       (1998) A functional serotonin transporter (5-HTT) polymorphism is
  induced movement disorders in schizophrenic patients.                   associated with psychosis in neuroleptic-free schizophrenics. Mol
  Psychopharmacology Berl 131: 174-179.                                   Psychiatry 3: 328-332.

  Arinami T, Li L, Mitsushio H, Itokawa M, Hamaguchi H, Toru              Malhotra AK, Goldman D, Ozaki N, Rooney W, Clifton A, Buchanan
  M (1996) An insertion/deletion polymorphism in the angioten-            RW, Breier A, Pickar D (1996) Clozapine response and the 5HT2C
  sin converting enzyme gene is associated with both brain                Cys23Ser polymorphism. Neuroreport 7: 2100-2102.
  substance P contents and affective disorders. Biol Psychiatry 40:
  1122-1127.                                                              Masellis M, Basile V, Meltzer HY, Lieberman JA, Sevy S, Macciardi
                                                                          FM, Cola P, Howard A, Badri F, Nothen MM, Kalow W, Kennedy JL
  Arranz M, Collier D, Sodhi M, Ball D, Roberts G, Price J, Sham P,       (1998) Serotonin subtype 2 receptor genes and clinical response to
  Kerwin R (1995) Association between clozapine response and              clozapine in schizophrenia patients. Neuropsychopharmacol 19:
  allelic variation in 5-HT2A receptor gene [see comments]. Lancet        123-132.
  346: 281-282.
                                                                          Minov C, Baghai TC, Schule C, Zwanzger P, Schwarz MJ, ZILL P,
  Arranz MJ, Munro J, Sham P, Kirov G, Murray RM, Collier DA,             Rupprecht R, Bondy B (2001) Serotonin-2A-receptor and -trans-
  Kerwin RW (1998) Meta-analysis of studies on genetic variation in       porter polymorphisms: Lack of association in patients with major
  5-HT2A receptors and clozapine response. Schizophr Res 32: 93-          depression. Neurosci Lett 303: 119-122.
  99.
                                                                          Pollock BG, Ferrell RE, Mulsant BH, Mazumdar S, Miller M, Sweet
  Arranz MJ, Mancama D, Kerwin RW (2001a) Neurotransmitter                RA, Davis S, Kirshner MA, Houck PR, Stack JA, Reynolds III, Kupfer
  receptor variants and their influence on antipsychotic treatment        DJ (2000) Allelic variation in the serotonin transporter promoter
  (Review). Int J Mol Med 7: 27-30.                                       affects onset of paroxetine treatment response in late-life depres-
                                                                          sion. Neuropsychopharmacol 23: 587-590.
  Arranz MJ, Munro J, Osborne SA, Collier D, Kerwin RW (2001b)
  Application of pharmacogenetics in psychiatry: personalisation of       Ram A, Guedj F, Cravchik A, Weinstein L, Cao Q, Badner JA, Goldin
  treatment. Expert Opinion in Pharmacotherapy 2: 537-542.                LR, Grisaru N, Manji HK, Belmaker RH, Gershon ES, Gejman PV
                                                                          (1997) No abnormality in the gene for the G protein stimulatory
  Baghai T, Schüle C, Zwanzger P, Minov C, Schwarz J, de Jonge S,         alpha subunit in patients with bipolar disorder. Arch Gen Psychiatry
  Rupprecht R, Bondy B (2001) Possible influence of the                   54: 44-48.
  insertion/deletion polymorphism in the angiotensin I-converting
  enzyme gene on therapeutic outcome in affective disorders.              Rasenick MM, Chaney KA, Chen J (1996) G protein-mediated
  Molecular Psychiatry 6: 258-259.                                        signal transduction as a target of antidepressant and antibipolar
                                                                          drug action: evidence from model systems. J Clin Psychiatry 57
  Basile VS, Masellis M, Badri F, Paterson AD, Meltzer HY, Lieberman      (Suppl 13): 49-55.
  JA, Potkin SG, Macciardi F, Kennedy JL (1999) Association of the
  MscI polymorphism of the dopamine D3 receptor gene with                 Rietschel M, Nothen MM, Albus M, Maier W, Minges J, Bondy B,
  tardive dyskinesia in schizophrenia. Neuropsychopharmacol 21:           Korner J, Hemmer S, Fimmers R, Moller HJ, Wildenauer D, Propping
  17-27.                                                                  P (1996) Dopamine D3 receptor Gly9/Ser9 polymorphism and
                                                                          schizophrenia: no increased frequency of homozygosity in German
  Belmaker RH, Bersudsky Y, Agam G, Levine J, Kofman O (1996)             familial cases. Schizophr Res 20: 181-186.
  How does lithium work on manic depression? Clinical and psycho-
  logical correlates of the inositol theory. Annu Rev Med 47: 47-56.      Rigat B, Hubert C, Alhenc GF, Cambien F, Corvol P, Soubrier F
                                                                          (1990) An insertion/deletion polymorphism in the angiotensin I-
  Bondy B, Malitas PN, Zill P, Boufidou F, Engel RR, Behrens S,           converting enzyme gene accounting for half the variance of serum
  Alevizos BE, Nikolaou C, Christodoulou GN (Submitted)                   enzyme levels. J Clin Invest 86: 1343-1346.
  Phospholipase Cγ1 in patients with bipolar disorder: possible
  involvement in lithium action and side effects. Psychiatric Genetics.   Scharfetter J, Chaudhry HR, Hornik K, Fuchs K, Sieghart W, Kasper
                                                                          S, Aschauer HN (1999) Dopamine D3 receptor gene poly-
  Catalano M (1999) The challenges of psychopharmacogenetics.             morphism and response to clozapine in schizophrenic Pakastani
  Am J Hum Genet 65: 606-610.                                             patients. Eur Neuropsychopharmacol 10: 17-20.

  Chen G, Hasanat KA, Bebchuk JM, Moore GJ, Glitz D, Manji HK             Schäfer M, Rujescu D, Giegling I, Guntermann A, Erfurth A, Bondy
  (1999) Regulation of signal transduction pathways and gene              B, Möller H (2001) Association of short-term response to
  expression by mood stabilizers and antidepressants. Psychosom           haloperidol treatment with a polymorphism in the dopamine D2
  Med 61: 599-617.                                                        receptor gene. Am J Psychiatry 158: 802-804.

  Cichon S, Nothen MM, Rietschel M, Propping P (2000) Pharma-             Segman R, Neeman T, Heresco-Levy U, Finkel B, Karagichev L,
  cogenetics of schizophrenia. Am J Med Genet Semin Med Genet             Schlafman M, Dorevitch A, Yakir A, Lerner A, Shelevoy A, Lerer B
  97: 98-106.                                                             (1999) Genotypic association between the dopamine D3 receptor
                                                                          and tardive dyskinesia in chronic schizophrenia. Mol Psychiatry 4:
  Fang J, Gorrod JW (1999) Metabolism, pharmacogenetics, and              247-253.
  metabolic drug-drug interactions of antipsychotic drugs. Cell Mol
  Neurobiol 19: 491-510.                                                  Shaikh S, Collier DA, Sham PC, Ball D, Aitchison K, Vallada H, Smith
                                                                          I, Gill M, Kerwin RW (1996) Allelic association between a Ser-9-Gly
  Franchini L, Serretti A, Gasperini M, Smeraldi E (1998) Familial        polymorphism in the dopamine D3 receptor gene and schizo-
  concordance of fluvoxamine response as a tool for differentiating       phrenia. Hum Genet 97: 714-719.
  mood disorder pedigrees. J Psychiatr Res 32: 255-259.
                                                                          Shirayama Y, Mitsushio H, Takashima M, Ichikawa H, Takahashi K
  Kapitany T, Meszaros K, Lenzinger E, Schindler SD, Barnas C, Fuchs      (1996) Reduction of substance P after chronic antidepressants
  K, Sieghart W, Aschauer HN, Kasper S (1998) Genetic                     treatment in the striatum, substantia nigra and amygdala of the
  polymorphisms for drug metabolism (CYP2D6) and tardive                  rat. Brain Res 739: 70-78.
  dyskinesia in schizophrenia. Schizophr Res 32: 101-106.
                                                                          Siffert W (1998) G proteins and hypertension: an alternative can-
  Kramer MS, Cutler N, Feighner J, Shrivastava R, Carman J, Sramek        didate gene approach. Kidney Int 53: 1466-1470.
  JJ, Reines SA, Liu G, Snavely D, Wyatt KE, Hale JJ, Mills SG, MacCoss
  M, Swain CJ, Harrison T, Hill RG, Hefti F, Scolnick EM, Cascieri MA,    Smeraldi E, Zanardi R, Benedetti F, Di BD, Perez J, Catalano M
  Chicchi GG, Sadowski S, Williams AR, Hewson L, Smith D, Rupniak         (1998) Polymorphism within the promoter of the serotonin
  NM, et al (1998) Distinct mechanism for antidepressant activity by      transporter gene and antidepressant efficacy of fluvoxamine [see
  blockade of central substance P receptors [see comments]. Science       comments]. Mol Psychiatry 3: 508-511.
  281: 1640-1645.


                                                                     182
www.cuwai.com




                                                                          L
  Smith MW, Mendoza RP (1996) Ethnicity and pharmacogenetics.
  Mt Sinai J Med 63: 285-290.

  Sodhi MS, Arranz MJ, Curtis D, Ball DM, Sham P, Roberts GW, Price
  J, Collier DA, Kerwin RW (1995) Association between clozapine
  response and allelic variation in the 5-HT2C receptor gene. Neuro-
  report 7: 169-172.

  Spina E, Sturiale V, Valvo S, Ancione M, Di Rosa AE, Meduri M,
  Caputi AP (1992) Debrisoquine oxidation phenotype and neuro-
  leptic-induced dystonic reactions. Acta Psychiatr Scand 86: 364-
  366.

  Steen VM, Lovlie R, MacEwan T, McCreadie RG (1997) Dopamine
  D3-receptor gene variant and susceptibility to tardive dyskinesia in
  schizophrenic patients [see comments]. Mol Psychiatry 2: 139-145.

  Suzuki A, Mihara K, Kondo T, Tanaka O, Nagashima U, Otani K,
  Kaneko S (2000) The relationship between dopamine D2 receptor
  polymorphism at the Taq1 A locus and therapeutic response to
  nemonapride, a selective dopamine antagonist, in schizophrenic
  patients. Pharmacogenetics 10: 335-341.

  Thompson J, Thomas N, Singleton A, Piggott M, Lloyd S, Perry EK,
  Morris CM, Perry RH, Ferrier IN, Court JA (1997) D2 dopamine
  receptor gene (DRD2) Taq1 A polymorphism: reduced dopamine
  D2 receptor binding in the human striatum associated with the A1
  allele. Pharmacogenetics 7: 479-484.

  Wieczorek SJ, Tsongalis GJ (2001) Pharmacogenomics: will it
  change the field of medicine? Cliica Chimica Acta 308: 1-8.

  Zill P, Baghai TC, Zwanzger P, Schule C, Minov C, Riedel M,
  Neumeier K, Rupprecht R, Bondy B (2000) Evidence for an
  association between a G-protein beta3-gene variant with depres-
  sion and response to antidepressant treatment. Neuroreport 11:
  1893-1897.




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   ORIGINAL INVESTIGATION/SUMMARY OF ORIGINAL RESEARCH

  The Activity of β-Hexosaminidase (uHex) and γ-Glutamyl-
  Transferase (uGGT) in Urine as Non-Invasive Markers of
  Chronic Alcohol Abuse: I. Alcohol-Dependent Subjects

                                        ´
  Ewa Taracha, Boguslaw Habrat, Piotr Woz niak, Jerzy Walkowiak,
  Bogdan Szukalski
  Institute of Psychiatry and Neurology, Warsaw, Poland


  Summary                                                 Introduction
  It has been demonstrated that in alcohol-dependent      Alcohol abuse is a rare example of a mental
  men the uHex test is one of the most powerful           disorder in which biochemical markers (of
  discriminating tools, while uGGT has a discrimina-      chronic alcohol drinking) can support the
  ting power similar to that of sHex but worse than       diagnosis. So-called "relapse markers" or markers
  that of uHex, sGGT and s%CDT. Receiver Operating        of recent alcohol intake may also be used in this
  Characteristic (ROC) areas under the curves (AUC)       setting to check the credibility of patients
  for uHex, uGGT, s%CDT, sHex and sGGT were               reporting abstinence, or to estimate the severity
  0.92, 0.79, 0.88, 0.79 and 0.92, respectively. Due to   of drinking.
  their good parameters, low cost, ease of use and non-
  invasive character the uHex and uGGT tests are          The widely used markers of chronic alcohol
  useful tools for the detection of chronic alcohol       drinking have a number of disadvantages that
  abuse.                                                  limit their usefulness. Most markers lack spe-
                                                          cificity, e.g. γ-glutamyltransferase (Anton et al
  Key words: urine β-hexosaminidase, urine                1995; Conigrave et al 1995; Meregalli et al 1995)
  γ-glutamyltransferase, serum γ-glutamyltransferase,     whereas the highly specific ones are usually
  CDT, biological markers of alcohol abuse.               expensive and require specialised equipment
                                                          (e.g. carbohydrate-deficient transferrin). Another
  Correspondence:                                         important drawback of the majority of popular
  Ewa Taracha, Ph.D.                                      markers is the necessity to draw blood samples.
  Department of Biochemistry                              Studies were undertaken recently to determine
  Institute of Psychiatry and Neurology                   whether the activity of selected enzymes in
  1/9 Sobieskiego Str.                                    urine, such as β-hexosaminidase and γ-gluta-
  02-957 Warsaw                                           myltransferase, might serve as markers of chro-
  Poland                                                  nic alcohol abuse. However, few studies have
  Tel: +48 22 6519311                                     been published. We have been able to find only
  Fax: +48 22 6519311                                     one paper on urinary γ-glutamyltransferase
  E-mail: habratb@ipin.edu.pl                             (uGGT) (Martines et al 1989). Research on uri-
                                                          nary β-hexosaminidase (uHex) comes from a
                                                          small number of sources, which include mainly
                                                          Polish (Habrat et al 1995a,b; Taracha et al
                                                          1999a,b; Wehr et al 1994, 1996) and Finnish
                                                          (Kärkkäinen 1990; Kärkkäinen et al 1990;
                                                          Kärkkäinen and Salaspuro 1991) centres.

                                                          The objective of this study was to assess the
                                                          value of β-hexosaminidase (uHex) activity and
                                                          γ-glutamyltransferase (uGGT) activity in urine as
                                                          chronic alcohol abuse markers, compared to the
                                                          following standard serum markers: the relative
                                                          amount of carbohydrate deficient transferrin
                                                          (s%CDT), γ-glutamyltransferase (sGGT) and β-
                                                          hexosaminidase (sHex).

                                                          Patients

                                                          The first group of alcohol-dependent subjects
                                                          (according to ICD-10 research diagnostic criteria)
                                                          comprised 69 men aged 23 to 63 years (mean age
                                                          43.19 ± 8.8) who underwent detoxification on a
                                                          hospital ward in the Institute of Psychiatry and
                                                          Neurology in Warsaw, Poland. The majority of


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  them (59.4%) had regularly drunk large quan-          Urinary creatinine was determined by the Jaffe
  tities of alcoholic beverages (mainly distilled)      reaction. The measurement of sHex and uHex
  during the three months before urine sampling.        was performed by the previously described spec-
  There are no validated data due to denial, other      trophotometric method (Marhun 1976; Taracha
  defence mechanisms and the specific kind of           et al 1999b) with the use of p-nitrophenyl N-
  chaotic drinking in a group. Patients drank 200-      acetyl β-D-glucosaminide as the substrate. An
  800g (mean 381 ± 211g) of ethanol on the last         activity unit was defined as the quantity of
  three days before cessation of drinking. They         enzyme which at 37ºC transformed 1 µmol of
  were admitted mainly without alcoholemia (45          substrate into p-nitrophenol during one minute.
  cases - 65.2%); in 15 cases (21.7%) the blood         The results for uHex were expressed as units per
  alcohol level measured by expiration was              1 mmol of creatinine (u/mmol creatinine), while
  between 0.1-1.0 per mille, and in the rest            results for sHex were expressed as units per 1 litre
  (13.1%) it was over 1 per mille.                      of serum (u/L). Measurements of uGGT and
                                                        sGGT were performed with the commercial
  The second group comprised 37 alcohol-                reagent by Alpha Diagnostics according to the
  dependent men aged 20 to 61 years (mean age           manufacturer's recommendations. The results
  40.84 ± 10.64) who had been abstinent for at          for uGGT were expressed as international units
  least six weeks (declared abstinence duration         per 1 mmol of creatinine (IU/mmol creatinine),
  ranged from 45 to 358 days, mean 118.8 ± 115.9        while results for sGGT were expressed as
  days). They were hospitalised in the rehabilita-      international units per 1 litre of serum (IU/L).
  tion unit and their sobriety had been controlled      Measurements of serum CDT were performed
  daily for at least the last six weeks.                with the Axis % CDT Turbidimetric Immuno-
                                                        assay by Bio Rad according to the recommended
  Patients in both groups were heavily dependent.       procedure. Readings were taken with the CODA
  The mean period of dependence was 18 and 16           analyser by Bio Rad. The results were presented
  years, respectively. The majority of patients had     as the ratio of carbohydrate-deficient transferrin
  a history of prior detoxification in hospital         to total transferrin, expressed as a percentage.
  (mean 4.3 and 2.3), and experiences with psy-         %CDT was used as it is a more valuable marker
  chotherapy of alcoholism (71% and 81%).               of high alcohol consumption than absolute CDT
                                                        values (Lesch et al 1996).
  Biochemical tests were performed one to three
  days after cessation of drinking. The same tests      In order to compare the means derived from the
  were performed on the sober alcoholic subjects        two groups, we used the Mann-Whitney’s test.
  after at least six weeks of abstinence. The           The correlations between the variables studied
  presented results of urinary tests performed on       were assessed with Spearman’s correlation
  alcohol-dependent subjects are mean values of         coefficients. The evaluation of the discrimi-
  measurements performed in two urine samples           nating potential of the studied tests was based
  obtained on two consecutive days because              on the Receiver Operating Characteristic (ROC)
  sporadic changes may occur in the quantity of         analysis (Zweig and Campbell 1993).
  enzyme levels in urine (Wensing et al 1990).
                                                        Results
  Methods
                                                        The following correlation coefficients were
  The following tests were performed on both            calculated in detoxified subjects: for uHex and
  groups: uHex, uGGT, s%CDT, sHex and sGGT.             uGGT, r=0.46, p=0.0001; for uHex and sGGT,
                                                        r=0.27, p=0.026; for sHex and sGGT, r=0.35,
  On the day of receipt of the urine sample, we         p=0.004.
  started its processing with a measurement of the
  creatinine concentration. If the creatinine           The correlation coefficients were as follows in
  concentration was below 3.5 mM, the sample            the abstinent subjects: for uHex and uGGT,
  was rejected as intentionally falsified or diluted.   r=0.4, p=0.015; for uHex and sGGT, r=0.4,
  The measurements were repeated on the next            p=0.02; and for sHex and sGGT, r=0.44, p=0.01.
  day’s sample. Urine enzyme activities were re-
  ferred to creatinine to reduce the effect of phy-     Correlation coefficients for the remaining para-
  siological factors like diuresis. Urine and serum     meters had low values and lacked statistical
  samples for uHex and sHex measurement were            significance.
  stored for a period of up to two weeks before
  processing, at a temperature of -20ºC. The            The mean values for uHex, uGGT, s%CDT, sGGT
  s%CDT measurements were performed within              and sHex found in detoxified and abstinent
  five months of receipt of the samples. Since the      alcohol-dependent patients are presented in
  freezing of samples may cause lower GGT               Table 1.
  activity by as much as 90% (Matteucci et al 1991;
  Matteucci and Giampietro 1994), the level of          All evaluated markers show higher values in de-
  this enzyme in urine and serum was determined         toxified alcohol-dependent patients than in ab-
  on the day of receipt of the samples.                 stinent subjects. The differences are statistically


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   ORIGINAL INVESTIGATION/SUMMARY OF ORIGINAL RESEARCH

  significant (p for uHex, uGGT, s%CDT, sHex and                                           We have grouped the corresponding ROC curves
  sGGT was found to be: 1.1 * 10-12, 6.2 * 10-7, 2.6 *                                     in Figure 1 in order to compare the discrimi-
  10-10, 9.5 * 10-7 and 5.9 * 10-12, respectively). Cut-                                   nating properties of the individual tests. The
  off levels were selected on the basis of ROC                                             comparison of the relative positions of the
  curves analysis.                                                                         curves shows that the uHex and sGGT tests
                                                                                           possess the highest discriminating potential.
  Table 2 shows cut-off values proposed for                                                Table 3 compares the areas under the curves
  diagnostic use along with their respective                                               (AUC), which characterise the respective discri-
  sensitivities and specificities.                                                         minating power of the tests.


                                                                                                         1,0
  Table 1

  The mean values for uHEX, uGGT, s%CDT, sHEX and sGGT tests in                                          0,8
  detoxified and abstinent alcohol-dependent patients

  Marker                   Abstinent                 Detoxified           p
                   n       mean ± SD         n       mean ± SD                                           0,6



                                                                                           sensitivity
  uHEX             37      0.34 ± 0.17       69      0.97 ± 0.75          1.1 * 10-12                                                             uHEX
  u/mmol                                                                                                                                          uGGT
                                                                                                         0,4
  creatinine                                                                                                                                      s%CDT
  uGGT             37      3.65 ± 0.95       69      5.83 ± 2.97          6.2 * 10-7                                                              sHEX
  IU/mmol
                                                                                                                                                  sGGT
  creatinine                                                                                             0,2
  s%CDT %          36      3.60 ± 1.02       66      7.66 ± 3.73          2.6 * 10 -10


  sHEX u/L         36      24.29 ± 5.74      69      37.07 ± 15.26        9.5 * 10-7
  sGGT IU/L        34      25.59 ± 14.51     69      118.70 ± 113.49      5.9 * 10-12
                                                                                                         0,0
                                                                                                               0,0   0,2   0,4            0,6   0,8       1,0
                                                                                                                             1 - specificity

  Table 2                                                                                  Figure 1
                                                                                           ROC curves in the group of alcohol-dependent patients
  Summary of selected cut-off values with their respective sensitivities and
  specificities for uHEX, uGGT, s%CDT, sHEX and sGGT tests in alcohol-
  dependent patients
                                                                                           The areas under the ROC curves that have the
                uHEX                uGGT          s%CDT       sHEX            sGGT         highest position, representing the uHex and
  Cut-off value 0.49                4.3            4,3 %      27 u/L          34 IU/L      sGGT tests, are larger than AUCs that have the
                u/mmol              IU/mmol                                                lowest position, which represent the uGGT and
                creatinine          creatinine                                             sHex tests (Table 3). The differences are statis-
  Sensitivity   0.85                0.71          0.77        0.72            0.83         tically significant. The curve for the s%CDT test
  Confidence    0.76-0.92           0.61-0.80     0.67-0.85   0.62-0.81       0.73-0.90    runs between the former and latter pair of
  interval*                                                                                curves. Its AUC shows no statistically significant
  Specificity   0.84                0.81      0.86            0.69            0.91         difference from the AUCs for the best tests (uHex
  Confidence    0.70-0.93           0.67-0.91 0.73-0.94       0.54-0.82       0.78-0.97    and sGGT) and the AUCs for the lowest curves
  interval*                                                                                (uGGT and sHex).

  * - confidence interval given for confidence level of 0.9                                The use of discriminative analysis allows simul-
                                                                                           taneous consideration of all tests for individual
                                                                                           subjects. This method of evaluation enabled us
  Table 3                                                                                  to correctly classify 87% of patients in the group.
                                                                                           The achieved sensitivity was 0.83, i.e. only
  Comparison of area under ROC curves (AUC) for uHEX, uGGT, s%CDT,                         slightly lower than the best of the studied tests
  sHEX and sGGT tests in alcohol-dependent patients                                        (0.87 for sGGT and 0.85 for uHex), while the
                                                                                           specificity was higher at 0.94.
  Marker                           AUC ± SE
  uHEX                             0.9197 ± 0.0265b,c                                      Eight of the detoxified patients started a rehabi-
  uGGT                             0.7944 ± 0.432c,d                                       litation program. Their uHex, uGGT, s%CDT,
  s%CDT                            0.8798 ± 0.0335                                         sHex and sGGT were measured twice: during
  sHEX                             0.7953 ± 0.0415a,b                                      detoxification and after several weeks of absti-
  sGGT                             0.9184 ± 0.0294a,d                                      nence. The obtained results and their compari-
                                                                                           son to the previously selected cut-off values are
  a-a
        p=0.015; b-b p=0.011; c-c p=0.013; d-d p=0.017                                     shown in Figure 2.


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                                                                                                                                                                                                  L
                      1,6       uHEX                                 8       uGGT                    16            s%CDT                      80       sHEX           120             sGGT

                      1,4                                            7                               14                                       70
                                                                                                                                                                      100
                      1,2                                            6                               12                                       60
                                                                                                                                                                          80


                                            IU/mmol creatinine
  u/mmol creatinine




                      1,0                                            5                               10                                       50




                                                                                             % CDT




                                                                                                                                                                   IU/L
                                                                                                                                        u/L
                      0,8                                            4                               8                                        40                          60

                      0,6                                            3                               6                                        30
                                                                                                                                                                          40
                      0,4                                            2                               4                                        20
                                                                                                                                                                          20
                      0,2                                            1                               2                                        10

                       0                                             0                               0                                        0                               0
                            I          II                                I              II                    I              II                    I          II                  I          II

                                1                                2                  3                     4                       5                    6                  7                  8

                                                                                                                        cut-off value
   Figure 1
   Values of uHEX, uGGT, s%CDT, sHEX, sGGT in alcohol-dependent patients examined during detoxification (I) and after several weeks of
   abstinence (II)



   The influence of alcohol consumption on the                                                                      Discussion
   studied markers was best demonstrated when
   patients who were tested during a period of alco-                                                                The most frequently used laboratory tests were
   hol abuse underwent follow-up testing after se-                                                                  characterised in reviews by Conigrave et al
   veral weeks' abstinence. A group of eight patients                                                               (1995), Musshoff and Dalrup (1998) and Sil-
   is too small for statistical evaluation; there was,                                                              lanaukee (1996). The authors published widely
   however, a marked decrease of uHex and s%CDT                                                                     varying data on the sensitivity and specificity of
   values after several weeks of abstinence. Test                                                                   these tests. For sGGT sensitivity and specificity
   results corresponding with the actual status of                                                                  range from 0.34 to 0.9 and 0.11 to 1, respecti-
   the patients (abnormal during detoxification                                                                     vely, while for CDT their ranges are 0.34 to 0.95
   and normal during abstinence) were found in six                                                                  and 0.82 to 1, respectively. Such discrepancies
   cases for uHex and s%CDT, in five cases for                                                                      are related to different doses of alcohol, different
   sGGT, in three for uGGT and in four for sHex.                                                                    cut-off values, performance of studies in
   Interestingly, two patients "erroneously quali-                                                                  differing populations, and comparing results in
   fied" by the uHex test (patients no. 2 and 8) were                                                               heavy drinkers to those in abstinent healthy
   also "erroneously qualified" by the sGGT test,                                                                   subjects, moderate drinkers or somatically ill
   while the s%CDT test qualified both subjects                                                                     subjects. The results of Lesch et al (1996) show
   correctly. The opposite was true for patients no.                                                                that CDT (a very good marker in alcohol-depen-
   4 and 7: the s%CDT value did not suggest                                                                         dent patients) remained unchanged in healthy
   alcohol abuse, while uHex and sGGT values were                                                                   subjects consuming even 80g of alcohol daily for
   concordant with the diagnosis. Out of three                                                                      three weeks. Therefore, apart from calculating
   patients who had misleading sGGT results (no. 2,                                                                 parameters which define the performance of the
   5 and 8), two were also "erroneously qualified"                                                                  studied tests (uHex and uGGT), we have com-
   by the uHex test, but all three had s%CDT test                                                                   pared their results with the results of tests
   results that were concordant with the diagnosis.                                                                 possessing an established value.
   The uGGT and sHex tests gave worse results in a
   small group of eight patients. However, those                                                                    Grzybowski and Younger (1997) have suggested
   tests had inferior parameters that resulted in                                                                   how to interpret the area under the ROC curve
   higher probability of false negative and false                                                                   when using it as a measure of the discriminatory
   positive results. The presented results support                                                                  power of tests. If the AUC is in the range of 0.5
   the opinion that two "independent" tests, such                                                                   to 0.7, the test has a poor discriminatory power,
   as uHex and s%CDT, or sGGT and s%CDT (there                                                                      while tests with an AUC of 0.7 to 0.9 are fairly
   is no correlation between uHex and s%CDT, or                                                                     good discriminators. Tests defined by an AUC of
   sGGT and s%CDT values) yield complementary                                                                       at least 0.9 may be rated as very good. ROC
   information. On the other hand, tests which                                                                      curves were made for sensitivity and specificity
   measure related parameters (a correlation exists                                                                 pairs for all cut-off points. It is the best method
   between uHex and sGGT) duplicate each other                                                                      to compare performance of tests, but one cut-off
   to a significant degree.                                                                                         point should be selected for diagnostic use. Its


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   ORIGINAL INVESTIGATION/SUMMARY OF ORIGINAL RESEARCH

  value depends on whether sensitivity or specifi-      suggesting that diagnosis based on two or more
  city is more important. It depends on the popu-       tests is more trustworthy, while the relevance of
  lation to be examined: for the same cut-off           individual tests may vary in individual patients
  levels, specificity would be higher for healthy       (Helander and Carlsson 1996; Helander et al
  teetotallers than for medically ill patients as the   1996; Mitchell et al 1997; Reynaud et al 1998).
  relevant group. Sensitivity would be higher in        This is true for statistically non-correlated
  alcoholics than in social drinkers. The reason for    markers (i.e. markers that have non-correlated
  this is that these tests are not ideal. We were       values). Our correlation coefficients show that
  looking for an optimal sensitivity/specificity        the most informative tests on alcohol dependent
  ratio on the basis of the ROC curve for each          patients are as follows: uHex paired with s%CDT
  group examined. Marker values fulfilling this         and sGGT paired with s%CDT. The two urinary
  criterion are proposed as cut-off levels for          tests (uHex and uGGT) provide us with similar
  diagnostic use in each group.                         information, as they have a high correlation
                                                        coefficient.
  Research on the use of uHex for the iden-
  tification of alcohol abusers was initiated in the    Our results show the usefulness of uHex and
  late 1980’s (Martines et al 1989). In later studies   uGGT as screening markers (detection of chronic
  it was demonstrated that such assaying of             alcohol use) in alcohol-dependent male patients.
  β-hexosaminidase both in urine and in serum is        The usefulness of these tests in female alcohol-
  useful for the monitoring of abstinence (i.e.,        dependent subjects and their specificity in
  non-chronic drinking) (Habrat 1995b; Kärk-            somatically ill patients should be examined. The
  käinen and Salaspuro 1991; Taracha et al              results of Kärkkäinen and Salaspuro (1991)
  1999a,b; Wehr et al 1996).                            suggested that uHex seems to be inferior to sHex
                                                        in the detection of recent alcohol use, but
  To date the test’s specificity has not been deter-    evaluation of these enzymes as relapse markers
  mined and its performance has not been com-           (markers of recent alcohol use) requires future
  pared with that of other alcohol abuse indices.       investigation. It should be taken into account in
  The area under the ROC curve for uHex is 0.92,        the evaluation of test accuracy that only a urine
  which speaks for a high discriminatory power.         sample is needed to perform the uHex and uGGT
  Assuming a cut-off level of 0.49 U/mmol of            tests, whereas the remaining tests require
  creatinine, the sensitivity and specificity of the    drawing of blood, which is inconvenient in case
  test are 0.85 and 0.84, respectively. The intra-      of multiple testing. The low price and the speed
  group comparison of the test’s parameters with        with which the test is performed are also of
  those obtained for tests characterised by a well-     substantial importance. The cost of reagents
  established usefulness, such as sGGT, s%CDT           needed for a single determination of Hex or GGT
  and sHex (Tables 2 and 3), places uHex among          in urine is much lower than in the case of the
  the best tests for alcohol-dependent subjects. Its    CDT test. The use of the latter is seriously limited
  parameters are comparable to those of sGGT,           by its price (Bell et al 1994; Reynaud et al 1998;
  slightly superior to those of s%CDT, and clearly      Stauber et al 1995; Rubio et al 1997; Meregali et
  superior to those of sHex.                            al 1995).

  We found only one article on the use of uGGT
  for identification of alcohol abuse (Martines et al
  1989), which reported a two-fold increase of
  uGGT activity in alcohol-dependent persons
                                                        References
  undergoing detoxification in comparison to
  abstinent alcohol-dependent persons. In the           Aithal GP, Thornes H, Dwarakanath AD, Tanner AR (1998)
  present study, we found an elevation of uGGT          Measurement of carbohydrate-deficient transferrin (CDT) in a
  that is slightly lower than that reported by          general medical clinic: is this test useful in assessing alcohol
                                                        consumption? Alcohol Alcohol 33: 304-309.
  Martines et al (1989). Based on the area under
  the ROC curve (Table 3), the capacity of uGGT to      Anton RF, Litten RZ, Allen JP (1995) Biological assessment of
  differentiate between drinking and abstaining         alcohol consumption. In: Allen JP, Columbus M (eds) Assessing
                                                        alcohol problems: a guide for clinicians and researchers. NIAAA
  alcohol-dependent subjects is comparable to that      Treatment Handbook Series 4. NIAAA, Bethesda, pp 31-39.
  of the sHex test but lower than that of uHex,
  s%CDT and sGGT.                                       Bell H, Tallaksen CME, Try K, Haug E (1994) Carbohydrate-deficient
                                                        transferrin and other markers of high alcohol consumption: a study
                                                        of 502 patients admitted consecutively to a medical department.
  We were able to measure the studied tests in          Alcohol Clin Exp Res 18: 1103-1108.
  eight of the alcohol-dependent subjects on two
  occasions: during detoxification and after several    Conigrave KM, Saunders JB, Whitfield JB (1995) Diagnostic tests for
  weeks of abstinence. The analysis of these data       alcohol consumption. Alcohol Alcohol 30: 13-26.
  and the assessment of discriminative power            Grzybowski M, Younger JG (1997) Statistical methodology: III.
  support the observations of other authors (Aithal     Receiver Operating Characteristic (ROC) curves. Acad Emerg Med
  et al 1998; Anton et al 1995; Helander and            4: 818-826.
  Carlsson 1996; Huseby et al 1997a,b; Rosman et
                                                        Habrat B, Czartoryska B, Górska D, Po Ÿniak M, Wehr H (1995a)
  al 1995; Salaspuro 1987; Sillanaukee et al 1998),     Próba wykorzystania β-heksozoaminidazy jako markera


                                                    188
www.cuwai.com




                                                                                                                                         L
  nadu¿ywania alkoholu w leczeniu uzale¿nienia. Doniesienie              related organ damage. Enzyme 37: 87-107.
  wstêpne. Postêpy Psychiatrii i Neurologii 4: 181-188.
                                                                         Sillanaukee P (1996) Laboratory markers of alcohol abuse. Alcohol
  Habrat B, Czartoryska B, Górska D, PoŸniak M, Wehr H (1995b)           Alcohol 31: 613-616.
  Urine β-hexosaminidase as a marker of sobriety monitoring.
  Alcohol Alcohol 30: 556-556.                                           Sillanauke P, Aalto M, Seppä K (1998) Carbohydrate-deficient
                                                                         transferrin and conventional alcohol markers as indicators for brief
  Helander A, Carlsson S (1996) Carbohydrate-deficient transferrin       intervention among heavy drinkers in primary health care. Alcohol
  and gamma-glutamyltransferase levels during disulfiram therapy.        Clin Exp Res 22: 892-896.
  Alcohol Clin Exp Res 20: 1202-1205.
                                                                         Stauber RE, Stepan V, Trauner M, Wilders-Trusching M, Leb G, Krejs
  Helander A, Carlson AV, Borg S (1996) Longitudinal comparison of       GJ (1995) Evaluation of carbohydrate-deficient transferrin for
  carbohydrate-deficient transferrin and gamma-glutamyltrans-            detection of alcohol abuse in patients with liver dysfunction.
  ferase: complementary markers of excessive alcohol consumption.        Alcohol Alcohol 30: 171-176.
  Alcohol Alcohol 31: 101-107.
                                                                         Taracha E, Habrat B, Baran-Furga H, Chmielewska K, WoŸniak P,
  Huseby N-E, Nilssen O, Erfurth A, Wetterling T, Kanitz RD (1997a)      Szukalski B (1999a) Zastosowanie oznaczania aktywnoœci β-
  Carbohydrate-deficient transferrin and alcohol dependency:             heksozoaminidazy w moczu i markerów alkoholizmu w surowicy
  variation in response to alcohol intake among different groups of      do identyfikacji osób nadu¿ywaj◊cych alkoholu wœród
  patients. Alcohol Clin Exp Res 21: 201-205.                            uzale¿nionych od opiatów uczestnicz◊cych w programie
                                                                         substytucyjnego leczenia metadonem. Alkoholizm i Narkomania
  Huseby N-E, Nilssen O, Kanitz RD (1997b) Evaluation of two             No 1 (34): 99-110.
  biological markers combined as a parameter of alcohol
  dependency. Alcohol Alcohol 32: 731-737.                               Taracha E, Habrat B, Chmielewska K, Baran H, Szukalski B (1999b)
                                                                         Zastosowanie oznaczania β-heksozoaminidazy w moczu do
  Kärkkäinen P (1990) Serum and urinary β-hexosaminidase as a            diagnostyki nadu¿ywania alkoholu przez osoby uzale¿nione od
  markers of heavy drinking. Alcohol Alcohol 25: 365-369.                opiatów bior◊ce udzia∆ w programie substytucyjnego leczenia
                                                                         metadonem. Psychiat Pol 33: 215 -224.
  Kärkkäinen P, Salaspuro M (1991) β-hexosaminidase in detection of
  alcoholism and heavy drinking. Alcohol Alcohol 26 (Suppl): 459-        Wehr H, Habrat B, Czartoryska B, Górska D, PoŸniak M (1994)
  464.                                                                   Zastosowanie oznaczania beta-heksozoaminidazy w moczu do
                                                                         diagnostyki nadu¿ywania alkoholu. Alkoholizm i Narkomania No 2
  Kärkkäinen P, Jokelainen K, Roine R, Suokas A, Salaspuro M (1990)      (16): 164-168.
  The effects of moderate drinking and abstinence on serum and uri-
  nary β-hexosaminidase levels. Drug Alcohol Dependence 25: 35-38.       Wehr H, Habrat B, Czartoryska B, Górska D, Woronowicz B (1996)
                                                                         Urinary β-hexosoaminidase activity as a marker for sobriety
  Lesch OM, Walter H, Antal J, Heggli DE, Kovacz A, Leitner A,           monitoring. Psychiat. Pol 30 (Suppl): 59-66.
  Neumeister A, Stumpf I, Sundrehagen E, Kasper S (1996)
  Carbohydrate-deficient transferring as a marker of alcohol intake: A   Wensing G, Neumann U, Ohnhaus EE, Heidemann HT (1990)
  study with healthy subjects. Alcohol Alcohol 31: 265-271.              Effect of antipyrine and phenobarbital on renal β-glutamyltrans-
                                                                         ferase excretion in human urine. Clin Pharmacol Ther 48: 575-581.
  Marhun D (1976) Rapid colorimetric assay of β-hexosaminidase
  and N-acetyl β-D-glucosaminide. Clin Chim Acta 73: 85-91.              Zweig MH, Campbel G (1993) Receiver-operating characteristic
                                                                         (ROC) plots: a fundamental evaluation tool in clinical medicine.
  Martines D, Morris AI, Gilmore IT, Ansari MA, Patel A, Quayle JA,      Clin Chem 39: 561-577.
  Billington D (1989) Urinary enzyme output during detoxification of
  chronic alcoholic patients. Alcohol Alcohol 24: 113-120.

  Matteucci E, Giampietro O (1994) To store urinary enzymes: how
  and how long? Kidney International 46 (Suppl 47): S58-S59.

  Matteucci E, Gregori G, Pellegrini L, Navalesi R, Giampietro O
  (1991) Effects of storage time and temperature on urinary
  enzymes. Clin Chem 37: 1436-1441.

  Meregalli M, Giacomini V, Lino S, Marchetti L, DeFeo T, Cappellini
  MD, Fiorelli G (1995) Carbohydrate-deficient transferrin in alcohol
  and nonalcohol abusers with liver disease. Alcohol Clin Exp Res 19:
  1525-1527.

  Mitchell C, Simpson D, Chick J (1997) Carbohydrate-deficient
  transferrin in detecting relapse in alcohol dependence. Drug
  Alcohol Dependence 48: 97-103.

  Musshoff F, Daldrup Th (1998) Determination of biological markers
  for alcohol abuse. J Chromatogr B 713: 245-264.

  Reynaud M, Hourcade F, Planche F, Albuisson E, Meunier MN,
  Planche R (1998) Usfulness of carbohydrate deficient transferrin in
  alcoholic patients with normal γ-glutamyltranspeptidase. Alcohol
  Clin Exp Res 22: 615-618.

  Rosman AS, Basu P, Galvin K, Lieber CS (1995) Utility of
  carbohydrate-deficient transferrin as a marker of relapse in
  alcoholic patients. Alcohol Clin Exp Res 19: 611-616.

  Rubio M, Caballeria J, Deulofeu R, Caballeria L, Gassó M, Parés A,
  Vilella A, Giménez A, Ballesta A, Rodés J (1997) Carbohydrate-
  deficient transferrin as a marker of alcohol consumption in male
  patients with liver disease. Alcohol Clin Exp Res 21: 923-927.

  Salaspuro M (1987) Use of enzymes for the diagnosis of alcohol-


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   ORIGINAL INVESTIGATION/SUMMARY OF ORIGINAL RESEARCH

  Inositol Treatment has no Effect on the
  Dexamethasone Suppression Test
  Joseph Levine, Uri Leventhal, Vadim Lerner, Robert H Belmaker
  Ministry of Health Mental Health Center, Faculty of Health Sciences, Ben Gurion University of
  the Negev, Beersheva, Israel

  Summary                                                  Introduction
  The dexamethasone suppression test (DST) is a            The dexamethasone suppression test (DST) is a
  widely studied state marker for endogenous depres-       widely studied state marker for endogenous
  sion. Several drugs cause false positives or negatives   depression. It was reported that DST non-
  in this test. Since inositol is a new treatment for      suppression is associated with endogenous or
  depression it is important to determine if it causes     melancholic depressions (Rush et al 1996), and
  artifacts in the DST. Five patients with major           that such a finding may suggest the need for
  depression diagnosed according to DSM-IV under-          biological interventions (Thase et al 1996). It was
  went a dexamethasone suppression test before and         also demonstrated that non-suppression is asso-
  after one and two weeks of 12 grams daily inositol       ciated with depressive symptomatology and that
  treatment. Three normal subjects underwent the           remission or significant symptomatic reduction
  same procedure before and after one week of inositol     is associated with the regaining of normal DST
  treatment. Four depressed patients and all three         response (Greden et al 1983).
  normal subjects demonstrated pretreatment dexa-
  methasone suppression of plasma cortisol. One or         Many depressed patients demonstrate hypo-
  two weeks of inositol treatment had no effect on post-   thalamus-pituitary-adrenal (HPA) system dys-
  dexamethasone cortisol plasma levels in patients or      regulation (Halbreich et al 1985a,b). One
  subjects. One depressed patient was a non-suppressor     manifestation is cortisol escape from dexa-
  before treatment and continued to show elevated post     methasone suppression in the DST (Rush et al
  dexamethasone cortisol levels after one week of          1996). A variety of drugs have been reported to
  inositol treatment. However, after two weeks on          modify DST results. These drugs include
  inositol, when substantial clinical improvement was      diphenylhydantoin, carbamazepine, pheno-
  noted, he converted to a normal DST. Chronic             barbital and lithium, along with spironolactone,
  inositol treatment does not seem to induce false         naloxone, alpha-1 mimetic agents, magnesium
  positive DST results.                                    trisilicate and oestrogen (Brooks et al 1972;
                                                           Carroll 1986; Dommisse et al 1985; Haque et al
  Key words: inositol, dexamethasone, cortisol,            1972). Antidepressants on the other hand were
  major depression.                                        found not to interfere with the results of this test
                                                           (Poland et al 1988), whereas their withdrawal
  Correspondence:                                          was associated with false positive DST results
  Robert H Belmaker, M.D.                                  (Carroll 1986).
  Beersheva Mental Health Center
  PO Box 4600                                              Inositol is a new antidepressant (Einat et al 1999;
  Beersheva                                                Levine et al 1995) and a key precursor of the
  Israel                                                   phosphatidylinositol (PI) second messenger
  Tel: + 972 7 6401 602                                    system. Twelve grams daily of inositol given for
  Fax: +972 7 6401 621                                     four weeks to depressed patients in a placebo-
  E-mail: belmaker@bgumail.bgu.ac.il                       controlled parallel design study showed
                                                           superiority over placebo. Also, a placebo-
                                                           controlled parallel design study of 12 grams
                                                           inositol given for six weeks in bipolar depressive
                                                           patients (Chengappa et al 2000) showed a
                                                           tendency towards superiority over placebo.
                                                           Inositol, like antidepressants of the SSRI group,
                                                           was reported in placebo-controlled double-blind
                                                           studies to be effective in panic disorder
                                                           (Benjamin et al 1995), obsessive-compulsive
                                                           disorder (Fux et al 1996) and bulimia (Gelber et
                                                           al 2001).

                                                           In order to use the DST as a possible predictor of
                                                           antidepressant effects in a study of inositol we
                                                           explored possible artifactual inositol effects on
                                                           the DST in depressed patients and normal
                                                           subjects.


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  Methods                                              sion levels of moderate and above had no
                                                       change in their depression level after two weeks
  Five hospitalized patients (four women and one       of inositol treatment. A fifth depressed patient
  man), mean age 44 years (range 44-58), who met       changed from moderate to mild after two weeks
  the DSM-IV criteria for a major depressive           of inositol treatment.
  episode and who were in good physical health
  and without a history of other psychiatric           Four of the five depressed patients and all three
  diagnoses, alcohol or drug abuse were recruited      normal subjects demonstrated normal post-
  into the study. No participants had substantial      dexamethasone suppression of plasma cortisol
  weight loss or gain, or were using any other         before inositol treatment. One and two weeks of
  drugs. No major recent life stress was reported in   inositol treatment had no effects on post-
  these subjects. All participants gave informed       dexamethasone cortisol plasma levels in these
  consent after full disclosure of the study           subjects. One depressed patient was a non-
  purposes and risks. An experienced clinician         suppressor at baseline and continued to show
  assessed the severity of depression as mild,         similar elevated post-dexamethasone cortisol
  moderate or severe.                                  levels following one week of inositol treatment,
                                                       but became a suppressor after two weeks on
  All three healthy volunteers (one woman, two         inositol, a time when a substantial clinical
  men), aged 40, 48 and 50 years, were in good         improvement was noted (from moderate to
  health, taking no drug treatments, had no recent     mild). Table 1 presents plasma cortisol levels at 9,
  substantial weight loss or gain and had not been     17 and 24 hours after dexamesthasone
  under any severe stress in the three months prior    administration.
  to, or during, the study. None of the volunteers
  had a personal or family history of psychiatric
  disorders. All gave signed informed consent. The     Table 1
  local ethics committee approved the protocol.
                                                       Inositol effects on post-dexamethone plasma cortisol levels (µg/dL)
  Cortisol was measured by competitive immuno-
  assay using direct chemoiluminescence techno-              Pretreatment            1 week of inositol 2 weeks of inositol
  logy in the Bayer (Tarrytown, NY) automated             Post-Dexamethasone        Post-Dexamethasone Post-Dexamethasone
  system (ACS-180). The intra- and interassay          Hour 8:00 16:00 23:00          8:00 16:00 23:00    8:00 16:00 23:00
  coefficients of variation were 5.8% and 8.5%,
  respectively. The laboratory routinely partici-      Depressed
  pates in the NEQAS quality control programme.        Patients
                                                       1        0.9   1.0    --        0.7    .09   .06         .09   .08    .09
  Dexamethasome 1.0 mg p.o. was administered at        2        2.1   2.2   2.0        1.7    1.5   1.4         1.3   1.5    1.6
  11 p.m. Serial blood samples were taken for the      3        1.3   0.9   0.9        2.3    1.4   0.8         1.5   1.0    1.2
  determination of plasma cortisol 9, 17 and 24        4        1.0   0.7   1.0        0.6    0.7   0.6          --   0.8    0.6
  hours after dexamethasone administration. (The       5        6.6   6.8   6.5        6.6    4.3   5.5         2.0   2.2    3.6
  last time point was not taken for the normal
  controls). This procedure was repeated after one     Controls
  and two weeks (one week only in the case of          6      0.9     .07              0.8    0.7
  normal controls) of inositol 12 g daily. Two         7      0.9     0.6              0.7    0.8
  weeks was chosen specifically in order to            8      0.6     0.6              0.8     --
  measure DST before clinical response and to
  determine if inositol, like carbamazepine for
  instance, might cause false positive DST
  results. Inositol treatment was added to ongoing     Discussion
  psychotropic treatment which had not led to
  clinical improvement. The psychotropic treat-        Inositol's antidepressant effect is reported to
  ment was not changed in the three weeks prior        appear after three to four weeks of treatment
  to the study, or during the study. The subjects      (Levine et al 1995), and no substantial beneficial
  received no psychotropic drug previously             effect of this drug on the depressive sympto-
  reported or suspected to induce DST changes.         matology is expected after two weeks (Levine et
  Inositol was given as a powder in juice or tea       al 1995). We thus did not expect to find
  twice daily.                                         antidepressant effects following two weeks of
                                                       inositol, and four of the five patients treated
  Results                                              with inositol for two weeks showed no change in
                                                       their depression level, whereas one patient’s
  DST non-suppression was defined as a plasma          depression was improved.
  cortisol concentration of >5±1 µg/dL nine hours
  after 1mg of dexamethasone administration. An        Myo-inositol was not found in this study to
  experienced clinician assessed the severity of       induce false positive DST results. Such false
  depression as mild, moderate or severe. Four of      positive results were previously reported for
  five depressed patients showing baseline depres-     diphenylhydantoin, carbamazepine and barbitu-


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   ORIGINAL INVESTIGATION/SUMMARY OF ORIGINAL RESEARCH

  rates, among other drugs (Carroll 1986), and the                        related functions. Arch Gen Psychiatry 42: 909-914.
  mechanism underlying such an effect was
                                                                          Haque N, Thrasher K, Werk EE, Jr, Knowles HC, Jr, Sholiton LJ
  suggested to involve the induction of hepatic                           (1972) Studies on dexamethasone metabolism in man: effect of
  enzymes responsible for dexamethasone meta-                             diphenylhydantoin. J Clin Endocrinol Metab 34: 44-50.
  bolism (Devanand et al 1984). Inositol is meta-
  bolized in the kidney and there are no reports                          Holub BJ (1986) Metabolism and function of myo-inositol and
                                                                          inositol phospholipids. Annu Rev Nutr 6: 563-597.
  which suggest that it causes the induction of
  hepatic enzymes (Holub 1986).                                           Levine J, Barak Y, Gonzalves M, Szor H, Elizur A, Kofman O,
                                                                          Belmaker RH (1995) Double-blind, controlled trial of inositol
  One depressed patient turned from a non-                                treatment of depression. Am J Psychiatry 152: 792-794.
  suppressor to a suppressor while on inositol                            Poland RE, Rubin RT, Lesser IM (1988) Serum dexamethasone
  treatment. However, since substantial decrease                          concentrations in endogenous depressives before, during, and
  in depression is known to be accompanied by                             after treatment: preliminary observations. Biol Psychiatry 23: 705-
                                                                          710.
  normalized DST (Rush et al 1996), the
  normalized DST results in this depressed subject                        Rush AJ, Giles DE, Schlesser MA, Orsulak PJ, Parker CR Jr,
  are probably related to the reported clinical                           Weissenburger JE, Crowley GT, Khatami M, Vasavada N (1996) The
  improvement. This subject demonstrated no                               dexamethasone suppression test in patients with mood disorders. J
                                                                          Clin Psychiatry 57: 470-484.
  substantial change of DST results from baseline
  to one week of inositol treatment, a time point at                      Thase ME, Dube S, Bowler K, Howland RH, Myers JE, Friedman E,
  which no clinical improvement was yet noted,                            Jarrett DB (1966) Hypothalamic-pituitary-adrenocortical activity
  suggesting that inositol also does not induce                           and response to cognitive behavior therapy in unmedicated,
                                                                          hospitalized depressed patients. Am J Psychiatry 153: 886-891.
  false negative results (Carroll 1986).




  References

  Benjamin J, Levine J, Fux M, Aviv A, Levy D, Belmaker RH (1995)
  Inositol treatment for panic disorder: a double-blind placebo-
  controlled crossover trial. Am J Psychiatry 152: 1084-1086.

  Brooks SM, Werk, EE, Ackerman SJ, Sullivan I, Thrasher K (1972)
  Adverse effects of phenobarbital on corticosteroid metabolism in
  patients with bronchial asthma. N Engl J Med 286: 1125-1128.

  Carroll BJ (1986) Informed use of the dexamethasone suppression
  test. J Clin Psychiatry 47: 10-12.

  Chengappa KNR, Levine J, Gershon S, Mallinger AG, Harden A,
  Vagnucci A, Pollock B, Luther J, Kupfer DJ (2000) Inositol in bipolar
  depression: a pilot, double-blind, placebo controlled random
  assignment clinical trial. Bipolar Disord 2: 47-55.

  Devanand DP, Pandurangi AK, Dewan MJ (1984) False-positive
  dexamethasone suppression test results related to antipsychotic
  drug withdrawal: case report. J Clin Psychiatry 45: 275-276.

  Dommisse CS, Hayes PE, Kwentus JA (1985) Effect of estrogens on
  the dexamethasone suppression test in nondepressed women. J
  Clin Psychopharmacol 5 :315-319.

  Einat H, Karbovski H, Korik J, Tsalah D, Belmaker RH (1999) Inositol
  reduces depressive-like behaviors in two different animal models of
  depression. Psychopharmacology 144: 158-162.

  Fux M, Levine J, Aviv A, Belmaker RH (1996) Inositol treatment of
  obsessive-compulsive disorder. Am J Psychiatry 153: 1219-1221.

  Gelber D, Levine J, Belmaker RH (2001) The effect of inositol
  treatment on bulimia nervosa and binge eating. Internat J Eating
  Disord 29: 345-348.

  Greden J, Gardner R, King D, Grunhaus L, Carroll B (1983)
  Dexamethasone suppression tests in antidepressant treatment of
  melancholia. Arch Gen Psychiatry 40: 493-500.

  Halbreich U, Asnis GM, Shindledecker R, Zumoff B, Nathan RS
  (1985a) Cortisol secretion in endogenous depression. I. Basal
  plasma levels. Arch Gen Psychiatry 42: 904-908.

  Halbreich U, Asnis, GM, Shindledecker R, Zumoff B, Nathan RS
  (1985b) Cortisol secretion in endogenous depression. II. Time-


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   VIEWPOINT

  Obsessive Compulsive Behaviour in Autism - Towards an
  Autistic-Obsessive Compulsive Syndrome?
  Ruth Gross-Isseroff1 , Haggai Hermesh2, Abraham Weizman3
  1
      Outpatient Department, Geha Psychiatric Hospital, Petach Tikva, Israel
  2
      Anxiety Disorders and Behavior Therapy Unit, Geha Psychiatric Hospital, Petach Tikva and Sackler
      Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
  3
      Research Unit, Geha Psychiatric Hospital, and Felsenstein Medical Research Center, Beilinson
      Medical Center, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel

  Summary                                                  Introduction
  A portion of autistic patients exhibit compulsive-like   A subgroup of patients suffering from autism
  behaviours. In addition it has been suggested that       display concomitantly patterns of obsessive
  serotonin plays a major role in both obsessive com-      compulsive behaviour (OCB). We will attempt
  pulsive disorder (OCD) and autistic disorder. Other      here to review data indicating the existence of
  neurohumors such as endogenous opioids and oxy-          common psychopathological similarities and
  tocin have also been implicated in the two disorders.    underlying neurobiological findings for the
  There is also some pharmacological overlap between       overlap zone of the two behavioural domains,
  the two disorders, as well as some similar neuro-        the putative autistic-compulsive syndrome.
  imaging studies. These similarities and overlaps have
  led us to propose a putative OCD-autistic disorder,      Behaviour
  which should be studied in greater detail.
                                                           It has frequently been noted that a substantial
  Key words: autistic disorder, obsessive compulsive       portion of the symptoms of autism, notably
  disorder.                                                repetitive, stereotyped behaviour patterns,
                                                           resemble some of the compulsive symptoms of
  Correspondence:                                          obsessive compulsive disorder (OCD) (e.g.
  Dr. Ruth Gross-Isseroff                                  Kobayashi and Murata 1998). Detailed pheno-
  Outpatient Department                                    menological research into the nature of these
  Geha Psychiatric Hospital                                obsessions and compulsions has revealed dif-
  P.O.B. 102                                               ferences between autism and OCD. Compulsive-
  Petach Tikva 49100                                       like behaviours such as repetitive ordering,
  Israel                                                   hoarding, touching, tapping and rubbing rituals
  Tel: +972 3 9258310                                      (i.e. compulsions) were found to be more fre-
  Fax: +972 3 9258388                                      quent in the autistic-compulsive subtype than in
  E-mail: bmruth@wisemail.weizmann.ac.il                   OCD, while obsessive thoughts with aggressive,
                                                           contamination, sexual, religious, symmetry and
                                                           somatic content (i.e. obsessions) were more
                                                           abundant in OCD and OCD-related disorders
                                                           (McDougle et al 1995a). It is of note that repe-
                                                           titive symptoms in autistic children are not a
                                                           clear indication of OCD (Baron-Cohen 1989).

                                                           Neurochemistry

                                                           Serotonin (5-HT) has been implicated in the
                                                           putative neurochemical substrate of both autism
                                                           and OCD. Monitoring of serotonin and its me-
                                                           tabolites in blood, urine and cerebrospinal fluid
                                                           (CSF) is the major approach utilized in this type
                                                           of neurochemical research. As most of the 5-HT
                                                           and its metabolites are produced in peripheral
                                                           organs rather than the CNS, and as in most of
                                                           the studies 5-HT was assessed in blood and urine,
                                                           these findings should be treated with caution.

                                                           Urine 5-hydroxy-indol acetic acid (5-HIAA) was
                                                           found to be elevated in autistic subjects as was
                                                           whole blood 5-HT (Yuwiler et al 1992; Warren
                                                           and Singh 1996; Herault et al 1996; Singh et al


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   VIEWPOINT

  1997; McBride et al 1998). This elevated level of    in both OCD (e.g. Altemus et al 1999) and
  whole blood 5-HT in autism has been reported to      autism (Insel et al 1999), but with inconclusive
  be familial (Leboyer et al 1999), as first-degree    results.
  relatives of autistic probands exhibit hyper-
  serotonaemia as well. This peripheral hyper-         Neuropharmacology
  serotonaemia was reflected also in the CNS by a
  brain-imaging study that demonstrated in-            Even though neuroleptic agents such as halo-
  creased serotonin synthesis in autistic children     peridol and risperidone (Sloman 1991; Sanchez
  (Chugani et al 1999), thus supporting the possi-     et al 1995; McDougle et al 1998b; Nicolson et al
  bility that whole blood 5-HT levels may reflect to   1998) have been shown to be effective in autism
  some extent brain levels of the neurotransmitter.    as well as in OCD (McDougle et al 2000), a
  In apparent discord with the hypothesis of hy-       number of studies have reported amelioration of
  perfunction of the 5-HT system in autism is the      obsessive compulsive symptoms and some of the
  finding that tryptophan depletion, leading to        core autistic symptoms with serotonin reuptake
  hyposynthesis and diminished availability of         inhibitors (SRIs) (Cook et al 1992; McDougle et
  serotonin, exacerbates autistic symptoms,            al 1992; Gordon et al 1993; Brodkin et al 1997).
  though not symptoms of repetitive behaviour          Moreover, the beneficial response was confined
  (McDougle et al 1996).                               to SRI and not to norepinephrine reuptake
                                                       inhibitors (Gordon et al 1993). This neuro-
  The only indication for increased 5-HT synthesis     pharmacological response is highly similar to the
  in OCD is the early finding of an elevated con-      neuropharmacology of OCD, where the medica-
  centration of 5-HIAA in the CSF (Thoren et al        tions of choice are serotonin reuptake inhibitors
  1980; Insel et al 1985) in OCD. However, not all     (Greist 1991; Montgomery and Manceaux 1992;
  studies found this elevation to be statistically     Zohar et al 1992).
  significant (Thoren et al 1980). Furthermore, this
  observation is somewhat in contrast to the           The significance of these findings is not clear - it
  finding of central serotonergic hypoactivity,        is possible that among autistic patients only
  which was shown in a number of pharmaco-             those with concomitant OCB respond to SRIs,
  logical challenge studies (Gross-Isseroff et al      but this question has not yet been directly
  1994). For example, exacerbation of OCD symp-        addressed.
  toms following meta-chloro-phenyl piperazine
  (mCPP) is not necessarily consistent with 5-HT       On the other hand, among SRI-resistant OCD
  hypofunction. Prolactin release following fenflu-    patients it has been proposed that anti-dopa-
  ramine challenge in autism was reported to be        minergic medications, such as those used in
  blunted in autistic patients (McBride et al 1989).   autism (e.g. risperidone), may be of benefit when
  A similar blunted prolactin response was found       added to SRIs (McDougle et al 1995b; McDougle
  in OCD patients in one study (Hewlett et al          1997). To date it seems that, while dopamine
  1992) but not in another (Hollander et al 1992).     blockers are effective in autistic disorder, they are
  It is possible that the peripheral hypersero-        ineffective when given alone in OCD.
  tonaemia in autism is accompanied by central
  hypoactivity of this system, in analogy to the       Neuroimaging
  findings related to OCD.
                                                       The most frequently documented brain structure
  In autistic patients challenge with sumatriptan, a   implicated in neuroimaging/regional cerebral
  specific 5-HT1D ligand, was found to exacerbate      blood flow studies in OCD is the caudate nucleus
  symptoms (Hollander et al 2000), similar to the      (Lucey et al 1995, 1997a,b; Rubin et al 1995;
  response observed in some OCD patients (Zohar        Baxter et al 1987; Hott Pian et al 1998; Cottraux
  1996). This implicates a specific subgroup of        et al 1996; McGuire et al 1994; Rauch et al 1994).
  serotonin receptors in both autism and OCD.          The next brain region, in order of frequency, in
  However, not all studies with sumatriptan            which changes in activity occur is the orbito-
  challenge in OCD reported exacerbation of            frontal cortex (Rauch et al 1994, 1997; McGuire
  symptoms (Pian et al 1998; Stein et al 1999). At     et al 1994; Breiter and Rauch 1996; Cottraux et al
  present it is still unclear whether the 5-HT         1996). The cingulate gyrus was also found to be
  findings in both OCD and autism have a causal        activated, as assessed by imaging studies, in OCD
  relationship to the disorders or whether they are    patients (McGuire et al 1994; Rauch et al 1994),
  simply epiphenomena.                                 as were portions of the temporal cortex (Breiter
                                                       and Rauch 1996; Zohar et al 1989; Cottraux et al
  A different neuropeptide, β-endorphin, was           1996; Lucey et al 1995) and the thalamus (Hott
  found to be decreased in both autistic and OCD       Pian et al 1998; Cottraux et al 1996; Lucey et al
  patients (Weizman et al 1988; Weizman et al          1995; McGuire et al 1994; Rauch et al 1994;
  1990), indicating yet another neurohumoral           Rubin et al 1992). Lately, one study reported
  similarity between the two syndromes. Naloxone       abnormal blood flow in the cerebellum of OCD
  challenge in OCD did not affect the pituitary-       patients (Hott Pian et al 1998); the cerebellum
  adrenal axis differently than in control subjects    has hitherto been used as the normalizing factor
  (Michelson et al 1996). Oxytocin was implicated      in most activation studies.


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  Less effort has been invested in functional           OCD, and the possibility of a diagnostic entity of
  neuroimaging of autism. The most consistent           autistic-compulsive syndrome, as was suggested
  findings are abnormalities of the cerebellum          for schizo-obsessive syndrome (Berman et al
  and, mainly, the vermis (Courchesne et al 1987;       1995; Poyurovsky et al 1999). Most probably this
  Muller et al 1999; Ciesielski et al 1997; Piven et    substrate involves a complex interaction be-
  al 1997; Ryu et al 1999; Schaefer et al 1996).        tween the serotonergic pathway and the limbic
  Others have recently reported abnormal blood          system structures implicated in repetitive and
  flow in the anterior cingulate gyrus (Haznedar et     stereotyped behaviour patterns. The further
  al 1997) and possibly the orbitofrontal cortex        elucidation of the biological basis that is
  (Baron-Cohen et al 1994), structures implicated       common to autism and OCD awaits controlled
  in the pathophysiology of OCD. The left               neurobiological experiments comparing patients
  posterior putamen was also implicated in autism       suffering from autism with and without OCB.
  (Siegel et al 1992).                                  The role of combined treatment of risperidone,
                                                        or other atypical neuroleptics, with SRIs in
  Taken together these findings indicate a partial      autistic-compulsive patients merits further large-
  neuroanatomical overlap between autism and            scale, double-blind controlled studies.
  OCD: the cerebellum, cingulate gyrus and
  possibly orbitofrontal cortex. However, these         At present it is still unclear whether OCD is a
  findings await corroboration on large cohorts of      central dimension in autistic disorder (in which
  patients suffering from autism, OCD or both. It       case there is not a real separate autistic-OCD
  is noteworthy that the caudate nucleus, pre-          syndrome) or a comorbid disorder in autistic dis-
  sumably involved in stereotypic behaviour, has        order (in which case the neurobiological overlap
  been implicated in autism only recently by            between the two may be artefactual), or whether
  neuroimaging data (Sears et al 1999), and found       there is a separate OCD-autistic syndrome with a
  to be correlated, in autistic patients, with com-     neurobiology that differs from that of each
  pulsions and rituals.                                 separate disorder.

  Overall, most of the imaging studies in the two       A set of case studies of well-characterized subsets
  disorders seem more disparate than not (cf.           of autistic patients with OCD are needed to
  Review of OCD findings in Saxena et al 1998).         substantiate the presence of OCD-autistic dis-
                                                        order as a clinical entity. Such autistic-OCD pa-
  Genetics                                              tients may be candidates for an initial trial with
                                                        selective SRIs before one with atypical neuro-
  A number of loci and genomic regions have been        leptics, or at least combination of selective SRIs
  proposed to contribute to the autistic syndrome.      with atypical antipsychotics.
  A preferential transmission of an allele of the
  serotonin transporter promoter (a VNTR (Varia-        Acknowledgements
  ble Number of Tandem Repeats) in intron 2 of          This work was supported by the Sarah and
  the upstream regulatory region) was reported in       Moshe Mayer Foundation for research (Tel-Aviv
  autism (Klauck et al 1997). While this result was     and Geneva).
  not replicated in an independent sample,
  another polymorphism of the promoter of this
  gene (short variant) was found to be linked with
  autism (Cook et al 1997). A polymorphism in the
  promoter region of the gene encoding the
  serotonin transporter protein (SLC6A4) was also       References
  shown to be linked to OCD (McDougle et al
                                                        Altemus M, Jacobson KR, Debellis M, Kling M, Pigott T, Murphy DL,
  1998a). No significant evidence of association or     Gold PW (1999) Normal CSF oxytocin and NPY levels in OCD. Biol
  linkage was found with two polymorphisms in           Psychiatry 45: 931-933.
  the serotonin transporter gene (a functional
  insertion-deletion polymorphism in the pro-           Baron-Cohen S (1989) Do autistic children have obsessions and
                                                        compulsions? Br J Clin Psychol 28: 193-200.
  moter and a variable number of tandem repeats
  in the second intron) (Maestrini et al 1999). The     Baron-Cohen S, Ring H, Moriarty J, Schmitz B, Costa D, Ell P (1994)
  relationship between this genotype, hyper-            Recognition of mental state terms. Clinical findings in children with
  serotonaemia and OCB in autistic-obsessive            autism and a functional neuroimaging study of normal adults. Br J
                                                        Psychiatry 165: 640-649.
  compulsive syndrome was not studied. Unfor-
  tunately, there are no family studies showing an      Baxter LR Jr, Phleps ME, Mazziotta JC, Guze BH, Schwartz JM, Selin
  indication of OCD/autism genetic overlap.             CE (1987) Local cerebral glucose metabolic rates in obsessive-
                                                        compulsive disorder. A comparison with rates in unipolar depres-
                                                        sion and in normal controls. Arch Gen Psychiatry 44: 211-218.
  Conclusion
                                                        Berman I, Kalinowski A, Berman SM, Lengua J, Green AI (1995)
  Taken together the results of neurochemistry,         Obsessive and compulsive symptoms in chronic schizophrenia.
  neuropharmacology, neuroimaging and neuro-            Compr Psychiatry 36: 6-10.
  genetics indicate the possible existence of a puta-   Breiter HC, Rauch SL (1996) Functional MRI and the study of OCD:
  tive common biological substrate for autism and       From symptom provocation to cognitive-behavioral probes of cor-


                                                    195
www.cuwai.com

                      L
   VIEWPOINT

  tico-striatal systems and the amygdala. Neuroimage 4: S127-138.       Klauck SM, Poustka F, Benner A, Lesch KP, Poustka A (1997)
                                                                        Serotonin transporter (5-HTT) gene variants associated with
  Brodkin ES, McDougle CJ, Naylor ST, Cohen DJ, Price LH (1997)         autism? Hum Mol Genet 6: 2233-2238.
  Clomipramine in adults with pervasive developmental disorders: a
  prospective open-label investigation. J Child Adolesc Psycho-         Kobayashi R, Murata T (1998) Behavioral characteristics of 187
  pharmacol 7: 109-121.                                                 young adults with autism. Psychiatry Clin Neurosci 52: 383-390.

  Chugani DC, Muzik O, Behen M, Rothermel R, Janisse JJ, Lee J,         Leboyer M, Philippe A, Bouvard M, Guilloud-Bataille M, Bondoux
  Chugani HT (1999) Developmental changes in brain serotonin            D, Tabuteau F, Feingold J, Mouren-Simeoni MC, Launay JM (1999)
  synthesis capacity in autistic and nonautistic children. Ann Neurol   Whole blood serotonin and plasma beta-endorphin in autistic
  45: 287-295.                                                          probands and their first-degree relatives. Biol Psychiatry 45: 158-
                                                                        163.
  Ciesielski KT, Harris RJ, Hart BL, Pabst HF (1997) Cerebellar hypo-
  plasia and frontal lobe cognitive deficits in disorders of early      Lucey JV, Costa DC, Blanes T, Busatto GF, Pilowsky LS, Takei N,
  childhood. Neuropsychologia 35: 643-655.                              Marks IM, Ell PJ, Kerwin RW (1995) Regional cerebral blood flow in
                                                                        obsessive-compulsive disordered patients at rest. Differential
  Cook EH Jr, Rowlett R, Jaselskis C, Leventhal BL (1992) Fluoxetine    correlates with obsessive-compulsive and anxious-avoidant
  treatment of children and adults with autistic disorder and mental    dimensions. Br J Psychiatry 167: 629-634.
  retardation. J Am Acad Child Adolesc Psychiatry 31: 39-45.
                                                                        Lucey JV, Burness CE, Costa DC, Gacinovic S, Pilowsky LS, Ell PJ,
  Cook EH Jr, Courchesne R, Lord C, Cox NJ, Yan S, Lincoln A, Haas      Marks IM, Kerwin RW (1997a) Wisconsin Card Sorting Task (WCST)
  R, Couchesne E, Leventhal BL (1997) Evidence of linkage between       errors and cerebral blood flow in obsessive-compulsive disorder
  serotonin transporter and autistic disorder. Mol Psychiatry 2: 247-   (OCD). Br J Med Psychol 70: 403-411.
  250.
                                                                        Lucey JV, Costa DC, Adshead G, Deahl M, Busatto G, Gacinovic S,
  Cottraux J, Gerard D, Cinotti L, Froment JC, Deiber MP, Le Bars D,    Travis M, Pilowsky L, Ell PJ, Marks IM, Kerwin RW (1997b) Brain
  Galy G, Millet P, Labbe C, Lavenne F, Bouvard M, Mauguiere F          blood flow in anxiety disorders. OCD, panic disorder with agora-
  (1996) A controlled positron emission tomography study of obses-      phobia, and post-traumatic stress disorder on 99mTcHMPAO single
  sive and neutral auditory stimulation in obsessive-compulsive dis-    photon emission tomography (SPET). Br J Psychiatry 171: 346-350.
  order with checking rituals. Psychiatry Res 60: 101-112.
                                                                        Maestrini E, Lai C, Marlow A, Matthews N, Wallace S, Bailey A,
  Courchesne E, Hesselink JR, Jernigan TL, Yeung-Courchesne R           Cook EH, Weeks DE, Monaco AP (1999) Serotonin transporter (5-
  (1987) Abnormal neuroanatomy in a nonretarded person with             HTT) and gamma-aminobutyric acid receptor subunit beta3
  autism. Unusual findings with magnetic resonance imaging. Arch        (GABRB3) gene polymorphisms are not associated with autism in
  Neurol 44: 335-341.                                                   the IMGSA families. The International Molecular Genetic Study of
                                                                        Autism Consortium. Am J Med Genet 88: 492-496.
  Gordon CT, State RC, Nelson JE, Hamburger SD, Rapoport JL
  (1993) A double-blind comparison of clomipramine, desipramine         McBride PA, Anderson GM, Hertzig ME, Sweeney JA, Kream J,
  and placebo in the treatment of autistic disorder. Arch Gen           Cohen DJ, Mann JJ (1989) Serotonergic responsivity in male young
  Psychiatry 50: 441-447.                                               adults with autistic disorder. Results of a pilot study. Arch Gen
                                                                        Psychiatry 46: 213-221.
  Greist JH (1991) Fluvoxamine treatment of obsessive compulsive
  disorder. Biol Psychiatry 29: 438.                                    McBride PA, Anderson GM, Hertzig ME, Snow ME, Thmpson SM,
                                                                        Khait VD, Shapiro T, Cohen DJ (1998) Effects of diagnosis, race,
  Gross-Isseroff R, Kindler S, Kotler M, Sasson Y, Dolberg O, Hendler   and puberty on platelet serotonin levels in autis and ental
  T, Zohar J (1994) Pharmacological challenges. In: Hollander E,        retardation. J Am Acad Child Adolesc Psychiatry 37: 767-776.
  Zohar J, Marazziti D, Olivier B (Eds) Current Insights in Obsessive
  Compulsive Disorder. Wiley, Chichester, pp 137-147.                   McDougle CJ (1997) Update on pharmacologic management of
                                                                        OCD: agents and augmentation. J Clin Psychiatry 58 (Suppl 12):
  Haznedar MM, Buchsbaum MS, Metzger M, Solimando A, Spiegel-           11-17.
  Cohen J, Hollander E (1997) Anterior cingulate gyrus volume and
  glucose metabolism in autistic disorder. Am J Psychiatry 154: 1047-   McDougle CJ, Price LH, Volkmar FR, Goodman WK, Ward-O’Brien
  1050.                                                                 D, Nielsen J, Bregman J, Cohen DJ (1992) Clomipramine in autism:
                                                                        preliminary evidence of efficacy. J Am Acad Child Adolesc
  Herault J, Petit E, Martineau J, Cherpi C, Perrot A, Barthelemy C,    Psychiatry 31: 746-750.
  Lelord G, Muh JP (1996) Serotonin and autism: biochemical and
  molecular biology features Psychiatry Res 65: 33-43.                  McDougle CJ, Kresch LE, Goodman WK, Naylor ST, Vlkmar FR,
                                                                        Cohen DJ, Price LH (1995a) A case-control study of repetitive
  Hewlett WA, Vinogradov S, Martin K, Berman S, Csernansky JG           thoughts and behavior in adults with autistic disorder and
  (1992) Fenfluramine sttimulation of prolactin in obsessive-           obsessive-compulsive disorder. Am J Psychiatry 152: 772-777.
  compulsive disorder. Psychiatry Res 42: 81-92.
                                                                        McDougle CJ, Fleischman RL, Epperson CN, Wasylink S, Leckman
  Hollander E, DeCaria CM, Nitescu A, Gully R, Suckow RF, Cooper        JF, Price LH (1995b) Risperidone addition in fluvoxamine-refractory
  TB, gorman JM, Klein DF, Liebowitz MR (1992) Serotonergic             obsessive-compulsive disorder: three cases. J Clin Psychiatry 56:
  function in obsessive-compulsive disorder. Arch Gen Psychiatry 49:    526-528.
  21-28.
                                                                        McDougle CJ, Naylor ST, Cohen DJ, Aghajanian GK, Heninger GR,
  Hollander E, Novotny S, Allen A, Aronowitz B, Cartwright C,           Price LH (1996) Effects of tryptophan depletion in drug-free adults
  DeCaria C (2000) The relationship between repetitive behaviors        with autistic disorder. Arch Gen Psychiatry 53: 993-1000.
  and growth hormone response to sumatriptan challenge in adult
  autistic disorder. Neuropsychopharmacology 22: 163-167.               McDougle CJ, Epperson CN, Price LH, Gelernter J (1998a) Evidence
                                                                        for linkage disequilibrium between serotonin transporter protein
  Hott Pian KL, Westenberg HG, den Boerr JA, de Bruin WI, Rijk PP       gene (SLC6A4) and obsessive compulsive disorder. Mol Psychiatry
  (1998) Effects of meta-chlorophenylpiperazine on cerebral blood       3: 270-273.
  flow in obsessive-compulsive disorder. Biol Psychiatry 44: 367-370.
                                                                        McDougle CJ, Holmes JP, Carlson DC, Pelton GH, Cohen DJ, Price
  Insel TR, Mueller EA, Alterman I, Linniola M, Murphy DL (1985)        LH (1998b) A double-blind, placebo-controlled study of
  Obsessive compulsive disorder and serotonin: is there a connec-       risperidone in adults with autistic disorder and other pervasive
  tion? Biol Psychiatry 20: 1174-1188.                                  developmental disorders. Arch Gen Psychiatry 55: 633-641.

  Insel TR, O’Brien DJ, Leckman JF (1999) Oxytocin, vasopressin, and    McDougle CJ, Epperson CN, Pelton GH, Wasylink S, Price LH
  autism: is there a connection? Biol Psychiatry 45:145-157.            (2000) A double-blind, placebo-controlled study of risperidone


                                                                   196
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                                                                                                                                         L
  addition in serotonin reuptake inhibitor-refractory obsessive-          pharmacol Biol Psychiatry 23: 613-624.
  compulsive disorder. Arch Gen Psychiatry 57: 794-801.
                                                                          Siegel BV Jr, Asarnow R, Tanguay P, Call JD, Abel L, Ho A, Lott I,
  McGuire PK, Bench CJ, Frith CD, Marks IM, Frackowiak RS, Dolan          Buchsbaum MS (1992) Regional cerebral glucose metabolism and
  RJ (1994) Functional anatomy of obsessive-compulsive pheno-             attention in adults with a history of childhood autism. J
  mena. Br J Psychiatry 164: 459-468.                                     Neuropsychiatry Clin Neurosci 4: 406-414.

  Michelson D, Altemus M, Galliven E, Hill L, Greenberg BD, Gold P        Singh VK, Singh EA, Warren RP (1997) Hyperserotoninemia and
  (1996) Naloxone-induced pituitary-adrenal activation does not           serotonin receptor antibodies in children with autism but not
  differ in patients with depression, obsessive compulsive disorder,      mental retardation. Biol Psychiatry 41: 753-755.
  and healthy controls. Neuropsychopharmacology 15: 207-212.
                                                                          Sloman L (1991) Use of medication in pervasive developmental
  Montgomery SA, Manceaux A (1992) Fluvoxamine in the                     disorders. Psychiatr Clin North Am 14: 165-182.
  treatment of obsessive compulsive disorder. Int Clin Psycho-
  pharmacol 7: 5-9.                                                       Stein DJ, Van-Heerden B, Wessels CJ, Van-Kradenburg J, Warwick J,
                                                                          Wasserman HJ (1999) Single photon emission computed
  Muller RA, Behen ME, Rothermel RD, Chugani DC, Muzik O,                 tomography of the brain with Tc-99m HMPAO during sumatriptan
  Mangner TJ, Chugani HT (1999) Brain mapping of language and             challenge in obsessive-compulsive disorder: investigating the
  auditory perception in high-functioning autistic adults: a PET study.   functional role of the serotonin auto-receptor. Prog Neuropsycho-
  J Autism Dev Disord 29: 19-31.                                          pharmacol Biol Psychiatry 23: 1079-1099.

  Nicolson R, Awad G, Sloman L (1998) An open trial of risperidone        Thoren P, Asberg M, Bertilsson L, Mellstrom B, Sjoqvist F, Traskman
  in young autistic children. J Am Acad Child Adolesc Psychiatry 37:      L (1980) Clomipramine treatment of obsessive compulsive disorder
  372-376.                                                                II: biochemical aspects. Arch Gen Psychiatry 37: 1289-1294.

  Pian KL, Westenberg HG, van-Megen HJ, den-Boer JA (1998)                Warren RP, Singh VK (1996) Elevated serotonin levels in autism:
  Sumatriptan (5-HT1D receptor agonist) does not exacerbate symp-         association with the major histocompatibility complex.
  toms in obsessive compulsive disorder. Psychopharmacology Berl          Neuropsychobiology 34: 72-75.
  140: 365-370.
                                                                          Weizman R, Gil-Ad I, Dick J, Tyano S, Szekely GA, Laron Z (1988)
  Piven J, Saliba K, Bailey J, Arndt S (1997) An MRI study of autism:     Low plasma immunoreactive beta-endorphin levels in autism. J Am
  the cerebellum revisited. Neurology 49: 546-551.                        Acad Child Adolesc Psychiatry 27: 430-433.

  Poyurovsky M, Fuchs C, Weizman A (1999) Obsessive-compulsive            Weizman R, Gil-Ad I, Hermesh H, Munitz H, Laron Z (1990)
  disorder in patients with first-episode schizophrenia. Am J             Immunoreactive beta-endorphin, cortisol, and growth hormone
  Psychiatry 156: 1998-2000.                                              plasma levels in obsessive-compulsive disorder. Clin Neuro-
                                                                          pharmacol 13: 297-302.
  Rauch SL, Jenike MA, Alpert NM, Baer L, Breiter HC, Savage CR,
  Fischman AJ (1994) Regional cerebral blood flow measured during         Yuwiler A, Shih JC, Chen CH, Ritvo ER, Hanna G, Ellison GW, King
  symptom provocation in obsessive-compulsive disorder using              BH (1992) Hyperserotoninemia and antiserotonin antibodies in
  oxygen 15-labeled carbon dioxide and positron emission tomo-            autism and other disorders. J Autism Dev Disord 22: 33-45.
  graphy. Arch Gen Psychiatry 51: 62-70.
                                                                          Zohar J (1996) Is 5HT1A involved in obsessive compulsive disorder?
  Rauch SL, Savage CR, Alpert NM, Dougherty D, Kendrick A, Curran         Eur Neuropsychopharmacol 6, S4: 54-55.
  T, Brown HD, Manzo P, Fischman AJ, Jenike MA (1997) Probing
  striatal function in obsessive-compulsive disorder: a PET study of      Zohar J, Insel TR, Berman KF, Foa EB, Hill JL, Weinberger DR (1989)
  implicit sequence learning. J Neuropsychiatry Clin Neurosci 9: 568-     Anxiety and cerebral blood flow during behavioral challenge.
  573.                                                                    Dissociation of central from peripheral and subjective measures.
                                                                          Arch Gen Psychiatry 46: 505-510.
  Rubin RT, Villanueva-Meyer J, Ananth J, Trajmar PG, Mena I (1992)
  Regional xenon 133 cerebral blood flow and cerebral technetium          Zohar J, Zohar-Kadoush RC, Kindler S (1992) Current concepts in
  99m HMPAO uptake in unmedicated patients with obsessive-                the pharmacological treatment of obsessive-compulsive disorder.
  compulsive disorder and matched normal control subjects. Deter-         Drugs 43: 210-218.
  mination by high-resolution single-photon emission computed
  tomography. Arch Gen Psychiatry 49: 695-702.

  Rubin RT, Ananth J, Villanueva-Meyer J, Trajmar PG, Mena I (1995)
  Regional 133xenon cerebral blood flow and cerebral 99mTc-
  HMPAO uptake in patients with obsessive-compulsive disorder
  before and during treatment. Biol Psychiatry 38: 429-437.

  Ryu YH, Lee JD, Yoon PH, Kim DI, Lee HB, Shin YJ (1999) Perfusion
  impairments in infantile autism on technetium-99m ethyl
  cysteinate dimer brain single-photon emission tomography: com-
  parison with findings on magnetic resonance imaging. Eur J Nucl
  Med 26: 253-259.

  Sanchez LE, Adams PB, Uysal S, Hallin A, Campbell M, Small AM
  (1995) A comparison of live videotape ratings: clomipramine and
  haloperidol in autism. Psychopharmacol Bull 31: 371-378.

  Saxena S, Brody Al, Schwartz JM, Baxter LR (1998) Neuroimaging
  and frontal-subcortical circuitry in obsessive-compulsive disorder.
  Br J Psychiatry (Suppl) 35: 26-37.

  Schaefer GB, Thompson JN, Bodensteiner JB, McConnell JM,
  Kimberling WJ, Gay CT, Dutton WD, Hutchings DC, Gray SB (1996)
  Hypoplasia of the cerebellar vermis in neurogenetic syndromes.
  Ann Neurol 39: 382-385.

  Sears LL, Vest C, Mohamed S, Bailey J, Ranson BJ, Piven J (1999) An
  MRI study of the basal ganglia in autism. Prog Neuropsycho-


                                                                     197
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   LETTERS TO THE EDITORS

  Launch of the Cardiac Safety in                               References
  Schizophrenia Group (CSISG)                                   FDA (2000a) Dear Doctor Letter on Thioridazine, 7 July.

                                                                FDA (2000b) Dear Doctor Letter on Mesoridazine, 22 September.
  Dora Kohen
  Consultant psychiatrist                                       Coucil Report CR57 (1997) The association between antipsychotic
                                                                drugs and sudden death. Report of the working group of the Royal
  Department of Psychiatry, Lancashire School of                College of Psychiatrists' Psychopharmacology Sub-Group.
  Postgraduate Medicine, Preston, Lancs, UK
                                                                Haverkamp W, Breithardt G, Camm AJ, Janse MJ, Rosen MR, Antze
  I am writing regarding the launch of a new group, the         Escande D, Franz M, Malik M, Moss A, Shah R (2000) The potential
                                                                for QT prolongation and proarrythmia by non-antiarrhythmic
  CSISG (Cardiac Safety in Schizophrenia Group). The            drugs: clinical and regulatory implications. Report on a policy
  CSISG is a multi-disciplinary panel of psychiatric and        conference of the European Society of Cardiology. Eur Heart J 21:
  cardiac professionals who are seeking to provide              1216-1231; published simultaneously in Cardiovasc Res 47: 219-
                                                                233.
  practical guidance for the mental health professionals
  on minimising cardiovascular risks for people with            Committee on Safety of Medicines - UK Medicines Control Agency
  schizophrenia.                                                (MCA) (1999) Suspension of availability of sertindole (serdolect).
                                                                Current Problems in Pharmacovigilance 25: 1.
  The group was formed initially in response to the need        Taylor Nelson Sofres Healthcare. Safety of antipsychotics - A survey
  for further guidance on QTc prolongation (abnormality         of 100 psychiatrists in the UK, December 2000.
  of cardiac conduction) and prescribing in schizophrenia,
  highlighted by the increasing number of antipsychotics
  that are receiving restrictions on their use due to this
  effect. These restrictions have included withdrawal and
  suspension of products or label warnings advising ECG
  monitoring (FDA 2000a, b; Committee on Safety of
  Medicines 1999). It is important to realise that QTc
  prolongation is not a class effect, but rather a spectrum     Reponse to Dr. S. Curran and
  of risk meaning that some antipsychotics may have a
  safer profile and have limited or no effect on QT.            Dr. K. Matthew's Letter to the
                                                                Editor (World J Biol Psychiatry
  Our group was launched in May 2001, along with the
  results of a survey of UK psychiatrists (Taylor et al
                                                                2001, 2: 107) Concerning
  2000) which showed that although 98% of psy-                  Yaryura-Tobias et al (2000)
  chiatrists are aware that certain antipsychotics put          Negative Outcome after
  schizophrenia patients at risk of potentially fatal
  cardiac disorders by significantly prolonging the QT
                                                                Neurosurgery for Refractory
  interval, awareness of exactly which antipsychotics can       Obsessive-Compulsive Spectrum
  have this detrimental effect is low.                          Disorder, World J Biol Psychiatry
  The Royal College of Psychiatrists has gone some way          1: 197-203.
  to help inform and provide guidance on this issue by
  recommending a thorough review of patients' medi-             José A Yaryura-Tobias
  cation and monitoring to help identify potential cardiac      Professor of Psychiatry
  problems (Council Report CR 57 1997). Advice to               New York University, New York, USA
  consider alternative antipsychotics has also been issued
  for clinicians in the prescribing information for             We the authors are very appreciative of the doctors'
  thioridazine (FDA 2000a). The European Society of             constructive comments. We had acknowledged in the
  Cardiology provided guidance saying that the                  paper the small sample size that prevents generalisation
  availability of clinically effective alternative drugs with   of the results and the lack of pre-surgical psychological
  a more favourable safety profile should be a regulatory       assessments in patients three and four. We realise that
  consideration for antipsychotics (Havercamp et al             comorbidity factors could perhaps affect the therapeutic
  2000).                                                        outcome. Finally, it is important to note that in this
                                                                sample depression with suicidal ideation or attempt did
  Although there is presently only limited guidance as to       not precede neurosurgery.
  the management of QT interval prolongation, it is
  important that guidelines are developed to help reduce                                            José A Yaryura-Tobias
  the risks in this area. As a result of recent developments,
  and in light of our research, we aim to be able to offer      Letters published in this Journal do not necessarily
  needed information and advice to other professionals          reflect the opinions of the Editors or the Editorial Board.
  involved in the care of patients with schizophrenia. We
  hope that our consensus statements on the implications
  of cardiac safety in the treatment of schizophrenia will
  soon appear and contribute to the management of
  schizophrenia.
                                             Dora Kohen


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  World J Biol Psychiatry (2001) 2, 201 - 204




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   CASE REPORT/CASE SERIES

  A Display of Hypomania in a Depressed Male
  in Response to Fluvoxamine
  Toshihiro Horiguchi1), 2), Shinkei Sai2)
  1)
       Department of Psychiatry and Behavioral Science, Tokyo Medical and Dental University
  2)
       Department of Psychiatry, Kanto Rosai Hospital, Kawasaki City, Japan


  Summary                                                 Introduction
  The present report describes the behavioural and        In some cases, when using an antidepressant
  psychological changes in a 55-year-old depressed        changes in mental state and neuromuscular
  male who displayed hypomania after the use of           symptoms (e.g. myoclonus, hyperreflexia, tre-
  fluvoxamine in addition to other antidepressant         mor) or an increase of the levels of serotonergic
  medications. The patient experienced his first major    agents occur in response to the administration;
  depressive episode after the bankruptcy of his com-     such responses are referred to as "serotonin syn-
  pany. When fluvoxamine was prescribed at a dose of      drome". Sternbach (1991) reviewed 12 reports on
  50 mg/day in addition to sulpiride at 150 mg/day        serotonin syndrome and identified eight
  and a 50 mg dose of trazodone before sleep seven        patients (21%) with hypomania. With respect to
  months after admission, grinning and a violation of     SSRIs (selective serotonin re-uptake inhibitors),
  ward rules occurred repeatedly. The patient became      literature reports claim that the drugs produce
  verbally aggressive to the staff and addicted to        fewer side effects than tricyclic antidepressants.
  gambling and alcohol. Six days after the cessation of   Ebert et al (1997) found one case each presenting
  fluvoxamine, his condition remitted. None of the        insomnia, auditory hallucinations and restless
  neuromuscular abnormalities indicative of serotonin     legs out of 200 cases, and they reported psy-
  syndrome appeared during the episode. Upon review       chosis-like side effects at an occurrence rate of
  of previous reports on manic switches induced by        0.04 per 100 remedy days. In contrast, several
  SSRIs and other antidepressants, we speculate that      reports have found cases exhibiting a manic
  the fluvoxamine accounted for his hypomania.            switch induced by fluoxetine, an SSRI. In this
                                                          paper the authors present a male exhibiting a
  Key words: depression, fluvoxamine, hypomania,          hypomanic change after starting fluvoxamine
  manic switch, SSRI.                                     and discuss his psychological changes.

  Correspondence:                                         Case presentation
  Toshihiro Horiguchi
  Department of Psychiatry and Behavioral Science         Our case was a 55-year-old male. He was the
  Tokyo Medical and Dental University                     second-born of three siblings. No information
  1-5-45 Yushima                                          regarding a psychiatric history was reported for
  Bunkyo City                                             him or for his family. After graduating from
  Tokyo 113-8519                                          elementary education, he had lived and worked
  Japan                                                   at a printing factory. He had two children but
  Tel: +81 3 3813 6111 Ext. 5243                          had been divorced when his first child was a pre-
  Fax: +81 3 5803 0135                                    teen. At the age of 40 he had established his own
  E-mail: horigti.psyc@tmd.ac.jp                          company. At 48 his bank lent him more than
                                                          100 million yen (over US$ 8.3 million) to
                                                          develop the company. The bankruptcy of one of
                                                          his customers, however, forced the bank to grant
                                                          him no more accommodations. When he was
                                                          late with one of his payments, the bank would
                                                          not accept payment and his company fell into
                                                          bankruptcy.

                                                          The patient began to experience insomnia and
                                                          was reluctant both to meet with others while
                                                          making the final arrangements for his company,
                                                          and for his sisters to bring him to our hospital.
                                                          The patient complained of insomnia, loss of
                                                          appetite, fatigue, headache, restlessness, anxiety,
                                                          depressed mood, suicidal ideation and anthropo-
                                                          phobia when he visited our hospital for the first
                                                          time. He scored 65 on Zung’s Self-Rating Depres-
                                                          sion Scale (SDS; Zung 1965). His doctor diag-
                                                          nosed him as having a major depressive episode.


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   CASE REPORT/CASE SERIES

  Four months of outpatient treatment yielded no                                       The patient forgot to take his medication on the
  significant improvement in his condition. Staff                                      15th day, and on the 19th and 21st day he came
  involved with him anticipated his suicidal                                           back to the hospital drunk late at night,
  ideation and therefore made arrangements for                                         although the staff had not given him permission
  inpatient treatment, and the patient consented                                       to leave. He confessed that he had gone to play
  to admittance to our hospital.                                                       the pachinko ball game and gamble, which he
                                                                                       had not done before. At this point, he began to
  On his admission ECG, EEG and cranial CT                                             show a grinning face. On the 25th and 26th day,
  found no abnormalities. Laboratory findings of                                       he left the hospital without permission from the
  liquid serum were in the normal range, except                                        staff and came back later than the promised
  for a high level of cholesterol (332 mg/dl) and                                      time. Again, on the 30th and 31st day he came
  triglycerides (191 mg/dl). When fluvoxamine                                          back drunk and late as he had been playing
  was prescribed, his cholesterol became well-                                         pachinko.
  controlled (200 ml/dl).
                                                                                       Fluvoxamine was eliminated from his medi-
  In the first several weeks after admission he often                                  cation regimen on the 34th day because he
  expressed no emotion, though he could commu-                                         repeatedly violated the rules of the ward. He was
  nicate with others, and he still complained of                                       still flippant, and on the second day after the
  dissatisfactory sleep and nightmares. However,                                       cessation of fluvoxamine (36 days after the
  by the time the judge was prepared to make a                                         drug’s introduction), he did not eat breakfast and
  determination regarding his bankruptcy within                                        forgot to take his medicine. He was still grinning,
  the next three months, he felt easy and was                                          although this stopped the next day. He went to
  leading the patient group in the ward. He then                                       the pachinko casino on the 56th day, but his
  applied for volunteer work to begin after dis-                                       facial expression had become calm. His con-
  charge. He attended ward activities regularly and                                    dition seemed improved, and he was therefore
  sometimes criticised staff members on the ward.                                      discharged on the 62nd day after the start of
  However, when the decision concerning the                                            fluvoxamine and began to visit the outpatient
  approval of his bankruptcy was accidentally                                          unit of the hospital.
  prolonged by an additional three months, and
  he then could not find a job, the patient became                                     The patient took the Rorschach test (Exner 1986)
  depressed again as a result.                                                         three times: 1 and 4 months after admission
                                                                                       (before using fluvoxamine) and 11 days after the
  Fluvoxamine at a dose of 50 mg/day was added                                         cessation of fluvoxamine. He gave responses
  to the patient’s previous medication regimen.                                        involving the movement of distorted human
  The morning after this change in prescription,                                       figures (MQ-): one on admission, three at the
  he expressed satisfaction with it because he had                                     fourth month, and one after the discon-
  slept well. Six days after the start of the flu-                                     tinuation.
  voxamine treatment he complained of constipa-
  tion, but he seemed to be less annoyed. He was                                       Discussion
  observed to smile. On the other hand, he
  continued to be verbally aggressive with the                                         This paper has described the case of a depressed
  ward staff at meetings (see Figure 1).                                               male displaying hypomanic change after adding
                                                                                       fluvoxamine to his treatment regimen, which
                                                                                       included other antidepressants. The patient be-
                                                                                       gan to exhibit flutters, joking, verbal aggressi-
                                                               (mg/day)                veness, and to violate ward rules. In addition, he
                                                               sulpiride 150           became absorbed in gambling and drinking.
                                                               trazodone 25       50
                                                               amitriptyline 10        These features are indicative of his hypomanic
                                                               alprazolam 1.2          state, and the patient displayed no abnormal
                                                               brotizolam 0,25         changes in body temperature, deep tendon
                                                               estazolam 1             reflexes, muscle tonus or body co-ordination. He
                                                               ethyl lofrazepate 1     scored 0 on the Serotonin Syndrome Scale
                                                               fluvoxamine 50          developed by Hegerl et al (Japanese version)
                            violation of ward rules                                    (Kaneda et al 2000), which proved that he did
                                    incompliance                                       not have systemic serotonin syndrome.

                                                               mood                    A review of reports on manic switches due to
                                                                                       tricyclic antidepressants suggested that persons
  0             4                            11       12   13 (months)
                                                                                       with a past history of bipolar disorders can ex-
  first visit   admission                                  discharge
                                                                                       perience manic episodes as a response to anti-
                                                                                       depressants (Wehr and Goodwin 1987). Some
  Figure 1
                                                                                       case studies have reported cases of manic switch
  Change in dose of medication and behavioural problems of our                         in response to SSRI if there is a past history or
  case.                                                                                family history of affective disorders (Diler and


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                                                                                                                      L
  Avci 1999; Kat 1996), and as a result of the SSRI    the Rorschach (Sax et al 1997). The present
  dose per se (Diler and Avci 1999; Hadley and         patient had something specific in his psycho-
  Cason 1989; Kat 1996) or of interaction with         pathology although he was a late-onset case. In
  other medications (e.g. carbonated lithium)          addition, he had psychosocial problems that had
  (Hadley and Cason 1989).                             somewhat indirect effects on the occurrence or
                                                       aggravation of his hypomanic state. His petition
  This patient, however, had never experienced a       was postponed, and he could not find a new job.
  manic episode and had no family history of
  bipolar disorders. In addition, there were no ab-    We therefore concluded that the patient’s manic
  normal findings regarding the CNS or hepatic         switch was not just medication-induced but a
  function. Most previous reports of manic switch      result of desperation when he recovered his
  have involved the use of fluoxetine, and there       psychic reality and found himself socially
  have been no other reports of serotonin syn-         suspended and unproductive. His predromal
  drome or other psychotic side effects, except for    state included psychotic features, which could
  one case claiming sleepiness as a result of the      have promoted (or "unmasked" (Dorevitch et al
  interaction of fluvoxamine and lithium (Evans        1993)) the occurrence of hypomanic change
  and Marwick 1990). There have been other             with the help of fluvoxamine. Future studies are
  reports of treatment with lithium (Öhman and         expected to explore the mechanism of manic
  Spigset 1993) and a 5-HT1A agonist (i.e.             switch and hypomanic state induced by SSRIs
  buspirone) (Baetz and Malcolm 1995) resulting        and to establish efficacious prevention of these
  in serotonin syndrome when used in conjunc-          states as the result of studies of psychological
  tion with fluvoxamine. In our case, the medica-      factors and follow-up of the cases.
  tions used concurrently with SSRI were sulpiride,
  trazodone and benzodiazepines, and we think it       Acknowledgement
  unlikely that these other medications induced        The authors thank Dr. D. Ebert for his beneficial
  his hypomanic state. Further, previous reports       comments.
  have noted an improvement in the manic switch
  in response to cessation or a reduced dose of SSRI
  (Dorevitch et al 1993). Our case had no more
  problematic behaviours or a grinning face after
  the cessation of fluvoxamine. These findings
  suggest that the patient had a transient disorder    References
  in serotonergic metabolism caused by a normal        Baetz M, Malcolm D (1995) Serotonin syndrome from fluvoxamine
  dose of fluvoxamine.                                 and buspirone. Can J Psychiatry 40: 428-429.

  George and Godleski (1996) reported a case of        Damore J, Stine J, Brody L (1998) Medication-induced hypomania
                                                       in Asperger’s disorder. J Am Acad Child Adolesc Psychiatry 37: 248-
  depression in a patient who experienced sero-        249.
  tonin syndrome after the use of 100 mg of
  trazodone before sleep in addition to fluoxetine.    Diler RS, Avci A (1999) SSRI-induced mania in obsessive-
  They speculated that combined serotonin re-          compulsive disorder. J Am Acad Child Adolesc Psychiatry 38: 6-7.
  uptake inhibition and/or m-chlorophenyl-             Dorevitch A, Frankel Y, Bar-Halperin A, Aronzon R, Zilberman L
  piperazine (a metabolite of trazodone with 5-        (1993) Fluvoxamine-associated manic behavior: a case series. Ann
  HT1 receptor agonist properties) underlay the        Pharmacother 27: 1455-1457.
  presentation of the syndrome. On the other           Ebert D, Albert R, May A, Merz A, Murata H, Stosiek I, Zahner B
  hand, in a study of the use of nortriptyline in      (1997) The serotonin syndrome and psychosis-like side-effects of
  children, Geller et al (1993) concluded that         fluvoxamine in clinical use - an estimation of incidence. Eur
  manic switch has no relation to the individual       Neuropsychopharmacol 7: 71-74.
  metabolic rate for tricyclic antidepressants. An     Evans M, Marwick P (1990) Fluvoxamine and lithium: an unusual
  important area of future study will be to measure    interaction. Br J Psychiatry 156: 286.
  the change in the density of SSRI in serum liquid
  and to analyse the gene involving serotonin          Exner JE Jr (1986) The Rorschach: a comprehensive system, Vol.1:
                                                       Basic foundations. 2nd edition. Wiley, New York.
  metabolism.
                                                       Geller B, Fox LW, Fletcher M (1993) Effect of tricyclic anti-
  Our patient took the Rorschach test three times.     depressants on switching to mania and on the onset of bipolarity
  Exner (1986) indicated that MQ- response is          in depressed 6- to 12-year-olds. J Am Acad Child Adolesc Psychiatry
                                                       32: 43-50.
  related to associated hallucinatory thoughts. Our
  patient's record showed MQ- upon admission           George TP, Godleski LS (1996) Possible serotonin syndrome with
  and even after remission of his hypomanic epi-       trazodone addition to fluoxetine. Biol Psychiatry 39: 384-385.
  sode, which is indicative of essentially deviated
                                                       Hadley A, Cason MP (1989) Mania resulting from lithium-
  thinking processes. Before using fluvoxamine,        fluoxetine combination. Am J Psychiatry 146: 1637-1638.
  his assertiveness would have made him pre-
  disposed to emotional disturbance, leading to        Kaneda Y, Ohmori T, Hegerl U (2000) The Japanese version of the
                                                       serotonin syndrome scale (JSSS). Brain and Nerves (No To Shinkei)
  behavioural problems. Typical-onset affective        52: 507-510 (Japanese).
  disordered patients show a more severe abnor-
  mal thought content than early-onset patients in     Kat H (1996) More on SSRI-induced mania. J Am Acad Child


                                                   203
www.cuwai.com




                                                                        L
   CASE REPORT/CASE SERIES

  Adolesc Psychiatry 35: 975.

  Öhman R, Spigset O (1993) Serotonin syndrome induced by
  fluvoxamine-lithium interaction. Pharmacopsychiat 26: 263-264.

  Sax KW, Strakowski SM, Keck PE Jr, McElroy SL, West SA, Bourne
  ML, Larson ER (1997) Comparison of patients with early-, typical-,
  and late-onset affective psychosis. Am J Psychiatry 154: 1299-
  1301.

  Sternbach H (1991) The serotonin syndrome. Am J Psychiatry 148:
  705-713.

  Wehr TA, Goodwin FK (1987) Can antidepressants cause mania
  and worsen the course of affective illness? Am J Psychiatry 144:
  1403-1411.

  Zung WWK (1965) A self-rating depression scale. Arch Gen
  Psychiatry 12: 63-70.




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