Psychoactive Plants - Estelle Levetin's Homepage by 2l0d49AD

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									Psychoactive Plants
Stimulants - III: Other Stimulants
Stimulants
   Cocaine
   Ephedrine
   Nicotine
   Khat - cathonine
   Betel nuts - arecoline
   Caffeine
Khat
Khat: stimulant from Catha Edulis
Alkaloids
   Khat contain cathinone and cathine, two
    phenylisopropylamine alkaloids which resemble
    amphetamine –
   Cathinone is the main alkaloid
       Produces amphetamine-like action - effects not distinguishable from
        amphetamine - a naturally occurring amphetamine - carbonyl group
        replaces methylene side chain
       Drug conditioned animals cannot distinguish cathinone from
        amphetamines
   Khat consumption induces mild euphoria and excitement,
    reduces appetite, increases heart rate and blood pressure
   Withdrawal symptoms can follow prolonged khat use include
    lethargy, depression, nightmares and tremor
Cathinone
   Functions by releasing catecholamines (esp.
    dopamine) from presynaptic storage sites
   Cathinone only present in fresh leaves – it
    degrades within 48 hrs
   After this time only cathine left
       Cathine also a stimulant but has a lower potential
        for abuse
Amphetamine    Meth-amphetamine




   Cathinone          Cathine




   Ephedrine     Pseudoephedrine
Betel Nuts
Betel nuts from the betel palm Areca catechu
Traditional Use
   Long history of use in Asia - recorded in 4th century
    in China
   Traditionally chewed
   Crushed betel nuts (from the betel palm) wrapped in
    pieces of betel leaf from the betel vine, Piper betel
    (in the pepper family - Piperaceae) along with lime
    and sometimes other flavorings
   Lime (CaCO3) needed to release alkaloid
Arecoline
   Many active ingredient in betel nuts is the
    alkaloid arecoline - although betel nuts have
    several other alkaloids
   Arecoline has also been shown to improve
    learning and memory
   Also traditional use for intestinal worms
       Used as an antihelminthic in veternary medicine
        today
Mode of Action
   Not completely understood
   Believed to affect the central and autonomic nervous
    systems - increases plasma concentrations of
    norepinephrine and epinephrine
   Evidence suggests also an inhibitor of GABA
    (gamma aminobutryc acid) uptake
   Also Piper betel leaf contains aromatic phenolic
    compounds which have been found to stimulate the
    release of catecholamines in vitro
Effects of Betel Chewing
   Stains mouth
   Possible carcinogen
       Betel chewing associated with throat, mouth, and
        esophagal cancers
   Betel chewing spreading
       Lime (CaCO3) needed to release arecoline
       However some chew it only for flavor not stimulating
        effect
       Also mixed with tobacco and it strongly interacts with
        tobacco
Caffeine
Coffee and Caffeine
   Made from seeds of Coffea arabica in the
    Rubiaceae
   Seeds occur in coffee berries (cherries of
    commerce)
Flowers and berries of
Coffea arabica
Coffee berries are picked by hand
by worker in Columbia
Coffea arabica native to Ethiopia
Ethnobotany and history
   Long history of use in Arab world
   Introduced to Europe in 1615
   By 1700 coffee houses popular throughout
    Europe
   Dutch established plantations in East Indies
    late in 17th century
   East Indies  Paris and Amsterdam 
    Caribbean Islans  South America
Caffeine
   Caffeine occurs naturally in the leaves, seeds or fruit
    of more than 60 plant species, of which coffee,
    cocoa-beans, tea, cola and guarana are the best
    known
   Like other stimulates, caffeine acts on CNS -
    noradrenergic receptors (norepinephrine)
   Promotes alertness and endurance
   Constricts blood vessels
   Increase heart beat
H   = theophylline   H   = theobromine
Caffeine Content of Common Products
   Drip coffee.....115 mg          Pepsi...............38 mg
   Tea..................40 mg      Surge...............51 mg
   Cocoa..............13 mg        Jolt Cola...........71 mg
   Coca Cola........46 mg          Excedrin...........65 mg
   Diet Coke.........46 mg         Anacin..............32 mg
   Dr. Pepper........40 mg         NoDoz............100 mg
   Mr. Pibb............41 mg       Vivarin............200 mg
   Mt. Dew............54 mg        Midol...............60 mg

								
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