Penuntun Praktikum Histologi Alimentary System by WayanSugiritama

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									   PENUNTUN PRAKTIKUM HISTOLOGI
        ALIMENTARY SYSTEM

     (HOW TO IDENTIFY THE MICROSCOPIC
     STRUCTURE OF ALIMENTARY SYSTEM)

                   DR. I WAYAN SUGIRITAMA
                   DR. I. G. N. SRI WIRYAWAN

HISTOLOGY DEPARTMENT, MEDICAL FACULTY OF UDAYANA UNIVERSITY



               sugiritama@gmail.com
           http://sugiritama.blogspot.com
                        MEDICAL FACULTY UDAYANA UNIVERSITY   9/25/2011




LIPS

 Note the :
 skin of the face
     keratinized   stratified squamous epithelium
     hair follicles

 red margin
 oral mucosa
     nonkeratinzed  stratified squamous epithelium
     labial minor salivary glands


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                         MEDICAL FACULTY UDAYANA UNIVERSITY   9/25/2011




TONGUE
   Posterior region of the tongue.
     Stratified squamous keratinized epithelium
     Covered with papillae, of which there are four principal
      kinds: Filiform, Fungiform, Circumvallate, and Foliate
      papillae.
   The circumvallate papillae
     Von Ebner's glands
     Taste buds are embedded within the epithelium of
      fungiform and circumvallate papillae
   Note the skeletal muscle

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                      MEDICAL FACULTY UDAYANA UNIVERSITY   9/25/2011




ESOPHAGUS
     Identify :
       the mucosa (epithelium, lamina propria, and
        muscularis mucosa),
       submucosa ,
       esophageal glands ,
       muscularis externa
       and adventitia .
     Note :
       the type of muscle in the muscularis externa to
        determine the region (upper, middle, lower) of
        the esophagus
       the presence of small arteries and veins in the
        adventitia .
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                        MEDICAL FACULTY UDAYANA UNIVERSITY   9/25/2011




CARDIA

   Identify :
     The transition from nonkeratinized stratified
      squamous epithelium to simple columnar
      epithelium.
     Identify the mucosa and its gastric pits

     Identify the cardiac glands on lamina propria

   Note :
     The  cardiac glands secrete mucous and are
      irregular tubes seen below the gastric pits .

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                          MEDICAL FACULTY UDAYANA UNIVERSITY   9/25/2011




FUNDIC
   Identify :
     The presence of fundic glands which contain parietal
      and chief cells , as well as mucous neck cells .
     The surface epithelium , gastric pits , neck , and base
      regions of the glands.
     Fundic glands are straight long, tubular glands with
      shallow pits. The greatest density of chief cells is in the
      basal region of each gland. Thus, the lower base region
      appears more basophilic than the neck and upper base
      region. The parietal cells are slightly eosinophilic.
     Observe the mucosa , muscularis mucosae ,
      submucosa , muscularis externa , and serosa .

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                        MEDICAL FACULTY UDAYANA UNIVERSITY   9/25/2011




PYLORIC

   Identify :
     deep pits and coiled pyloric glands which are composed
      of predominantly mucous acinar cells
     The lamina propria is heavily infiltrated with immune
      cells such as lymphocytes and plasma cells.
     Examine the mucosa , submucosa , muscularis
      mucosae , muscularis externa , and serosa .
     Observe that the most dominant layer of the muscularis
      externa is the circular layer which forms the pyloric
      sphincter.

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                              MEDICAL FACULTY UDAYANA UNIVERSITY   9/25/2011


    DUODENUM
   Identify:
   Observe Brunner's glands in the submucosa.
   Examine the inner circular and outer longitudinal layers of smooth
    muscle in the muscularis externa .
   Observe the location of the muscularis mucosae , which is often
    disrupted by Brunner's glands.
   Note the large broad villi of the mucosa. The core of the villus is an
    extension of the lamina propria and also contains a blind ending
    lymphatic capillary, the lacteal .
   Study the simple columnar epithelium populated by goblet cells and
    the absorptive enterocytes with apical microvilli . The goblet cells
    increase in number from the proximal to distal small intestine.
   The cytological preservation in the crypts of Lieberkuhn is not very
    good and therefore it is difficult to observe the many mitotic figures
    that are normally present.
   Paneth cells may be observed at the base of the crypts but are not very
    well preserved. Recall that the crypts are longer in the duodenum than
    in the jejunum. Study the Auerbach's (myenteric) plexi between the
    layers of the muscularis externa.

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                              MEDICAL FACULTY UDAYANA UNIVERSITY   9/25/2011




JEJENUM
   The folds, containing a core of submucosa, are the plicae circulares
    (valves of Kerckring). The plicae circulares are most prominent in the
    distal duodenum and jejunum.
   Observe the layers of the wall of the jejunum . Note the absence of
    glands in the submucosa, which is a characteristic feature of the
    jejunum.
   Observe the crypts of Lieberkuhn . Paneth cells are found at the base
    of the crypt and are identified by their eosinophilic granules.
   Examine the villi on this slide with the core of lamina propria
    containing a lacteal .
   Observe the goblet cells and notice the greater number as compared
    to the duodenum. Study the muscularis externa and serosa




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    ILEUM
                             MEDICAL FACULTY UDAYANA UNIVERSITY   9/25/2011




   Presence of large groups of lymphatic nodules in the lamina propria
    called Peyer's patches .
   The plicae circulares (valves of Kerckring) in this slide are not as
    prominent as those found in the duodenum and jejunum.
   Observe the villi and compare to the duodenum and jejunum. Here
    the villi are much more leaf-like in appearance when compared to
    the finger-like villi of the duodenum and jejunum.
   Note the muscularis mucosa and the absence of glands in the
    submucosa.
   Examine the muscularis externa and recall the inner circular and
    outer longitudinal organization.
   Study the crypts of Lieberkuhn and observe paneth cells . Observe
    the density of goblet cells covering the villi and lining the crypts of
    Lieberkuhn. Goblet cells are most numerous in the terminal ileum.
   Finally, observe the serosa .


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                       MEDICAL FACULTY UDAYANA UNIVERSITY   9/25/2011


    COLON
   There are no villi or plicae circularis in the large
    intestine.
    The simple columnar epithelium has abundant goblet
    cells interspersed with absorptive cells .
   The crypts of Lieberkuhn are larger than in the small
    intestine.
   Present of enteroendocrine cells (argentaffin or APUD
    cells) at the base of the crypts.
   Note the absence any glands in the submucosa .
   Examine the muscularis mucosae and the muscularis
    externa .
   Next, observe the serosa .
    Find Auerbach's plexi (between the layers of the
    muscularis externa) and Meissner's plexi (beneath the
    muscularis mucosae within the submucosa).
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                       MEDICAL FACULTY UDAYANA UNIVERSITY   9/25/2011




APENDIX

    Note the absence of villi, few crypts, reduced
     surface area for absorption, and angular lumen.
    The lamina propria and submucosa are heavily
     infiltrated with lymphatic tissue; be able to locate
     lymphatic nodules .
    Note the absence of any glands in the submucosa.
    The muscularis mucosae is difficult to see.
     Examine the muscularis externa with inner circular
     and outer longitudinal layers. Observe the serosa


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