Histology of Stomach
Learning Objectives
At the end of lecture , the student should be able to describe:
1. Different regions of stomach, grossly and histologically
2. Various layers of the wall of stomach
3. Different glands and the various kind of cells present in them
STOMACH
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Gross anatomically divided into 4 regions, i.e. cardiac, fundus, body & pylorus.
Histologically divided into 3 regions, because the fundus & body have identical
microscopic features.
Stomach wall consists of usual 4 coats, i.e. mucosa, submucosa, muscularis externa and
serosa.
In empty stomach, the mucosa & submucosa are thrown into numerous longitudinal
folds called ”rugae”.
In stomach filled with food, these folds flattened out.
STOMACH
STOMACH
MUCOSA
Epithelium:
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Simple columnar that invigilates to variable extends into LP forming Gastric pits.
At bottom of each pit are several openings of br. tubular glands, lying in the LP.
Lamina propria (LP):
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Composed of loose CT, interspersed with smooth muscle & lymph cells b/w them.
It is literally pack with glands
Muscularis mucosae:
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In which smooth muscle fibers are arranged into inner- circular & outer longitudinal
layers.
SUBMUCOSA
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Composed of dense CT, containing blood & lymph vessels, & submucosal plexus of
nerves, but no gland
MUSCULARIS EXTERNA
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Composed of 3 layers of smooth muscle inner-oblique, middle-circular,& outerlongitudinal.
Myenteric plexus lie between middle & outer layers.
SEROSA
Thin layer of CT & mesothelium.
Layers of wall of stomach
GLANDS OF STOMACH
3 types – according to distribution & structural difference.
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Cardiac glands. Extension 1/3, terminal portions are coiled. Secret mucus & lysozyme.
Pyloric glands. Extension ½, located in pyloric antrum & canal, they are short coiled
(reverse to cardiac). secrete mucus & lysozyme.
G - cells – gastrin, stimulate HCl.
D - cells – somatostatin, inhibits release of gastrin.
REGIONS OF STOMACH & THEIR HISTOLOGICAL
STRUCTURE
GLANDS OF STOMACH
3. Gastric glands. extension ¼ of mucosal thickness, 3 to 7
glands open into bottom of each pit.
regions, i.e. neck, isthmus (body)
& base.
- 5 types of cells are present in the glands
 Stem cells.
 Mucus neck cells.
 Parietal (oxyntic i.e. acid forming) cells.
 Chief (zymogenic) cells.
 Entero-endocrine cells.
- Each gland has 3
CELLS OF GASTRIC GLANDS
STEM CELL
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Few in number and found in neck.
Low columnar cells.
Have high rate of mitosis.
MUCOUS NECK CELLS
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Located in neck.
Irregular in shape.
Contain mucinogen granules.
CELLS OF GASTRIC GLANDS
PARIETAL (OXYNTIC) CELLS
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Found in body & neck.
Rounded or pyramidal cells
Intensely eosinophilic cytoplasm.
Presence of intracellular canaliculi.
Produce HCl & intrinsic factor.
CHIEF (ZYMOGENIC) CELLS
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Found in base of gland.
Pyramidal cells.
Apical region is acidophilic and basal region is basophilic.
Contain pepsinogen granules.
CELLS OF GASTRIC GLANDS
ENTEROENDOCRINE CELLS
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Under L/M: Pyramidal cells located in the bases of the glands.
Not easily recognized in routine preparations.
May sometimes be identified by their peripheral location, and clear, unstained
cytoplasm.
Under E/M: Each has a large euchromatic nucleus.
Cytoplasmic organelles are sparse.
Basal region contains small secretary granules. Which are released into the capillaries
(present in lamina propria).
- some stain well by
silver nitrate – Argentaffin cells.
- many stain
well by potassium dichromate – Enterochromaffin.
- many other do not stain by either of these two methods
Section of the gastric glands in fundus of stomach
Photomicrograph Note the superficial mucussecreting epithelium.
Parietal cells (light-stained) predominate in the mid
and upper regions of the glands.
Chief (zymogenic) cells (dark-stained) predominate
in the lower region of the gland.
MM, muscularis mucosae.
Section of the gastric glands
Photomicrograph of a mucus-secreting surface epithelium(A)
and mucous neck cells intercalated between oxyntic (parietal)
cells located in the mid portion of the gastric gland (B).
Abundant capillaries can be seen.
Basal portion of gastric gland in the fundus
Photomicrograph This section shows parietal cells
rich in mitochondria and their characteristic
intracellular canaliculi (arrowheads).
Chief cells show red secretory granules in their
cytoplasm.