14. Stomach
Section of the gastric glands
in the fundus of the
stomach.
Note the superficial
mucus-secreting
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.
15. Histology LAYERS
1. Mucosa
• The first main layer.
• consists of an epithelium
(simple columnar
epithelium), the lamina
propria underneath, and a
thin layer of smooth muscle
called the muscularis
mucosae
2. Submucosa
• Lies under the mucosa
• Consists of fibrous
connective tissue,
separating the mucosa
from the next layer.
• The submucosal nerve
plexus is in this layer.
16. 3. Muscularis externa
• Consists of three
layers:
i. inner oblique layer
– responsible for creating the
motion that churns and physically
breaks down the food
i. middle circular layer
– constricted at the pylorus forming
pyloric sphincter, which controls
the movement of chyme into the
duodenum
i. outer longitudinal layer
– Auerbach's plexus is found
between this layer and the
middle circular layer.
17. 4. Serosa
• outside the muscularis
externa
• consisting of layers of
connective tissue
continuous with the
peritoneum
19. Normal Histological Features:
• The gastric mucosa consists of surface
epithelium, gastric pits and gastric glands.
• The gastric glands extend from the
muscular mucosa extend into the stomach
lumen via gastric pits.
• The cells lining the surface and gastric
pits are identical throughout the stomach
• Glands differ in different regions of the
stomach.
• Gastric pits occupy approximately 25%
of the mucosa. Pits lie parallel to one
another.
• There is more lamina propria separating
the pits than between the glands.
• In normal gastric biopsy degree of pit
and glandular separation should be same
throughout the biopsy.
20.
21.
22. • Cardia-
Small area of predominantly
mucus secreting glands
surrounding the entrance of the
esophagus.
• The pits are shorter than the
antropyloric pits.
•Fundus and body
Major histological region.
Consists of straight, tubular
glands.
Strands of muscularis
mucosae extend between the
glands from the base.
The glands secrete gastric
juices as well as protective
mucus.
23. • FUNDAL PART OF THE
STOMACH
Stained with
haematoxylin and eosin 1 -
tunica mucosa
2 - tunica submucosa
3 - tunica muscularis propria
4 - tunica serosa
5 - epithelium of the mucosa
6 - lamina propria of the
mucosa (contains glands)
7 - muscularis mucosae
24. • Pylorus-
Branched glands open into
deep irregular shaped pits.
Composed of mucus
secreting cells.
• Mucus secreted by pyloric
glands lubricate and protect
entrance to the duodenum.
Scattered 'G' cells (endocrine
cells), secrete gastrin.
• Note:
Gastric mucosa forms a
barrier to diffuse of gastric
acid from the gastric lumen.
25. PYLORIC PART OF THE
STOMACH
Stained with
haematoxylin and eosin 1
- tunica mucosa
2 - tunica submucosa
3 - tunica muscularis
propria
5 - lamina propria of the
mucosa
(contains glands)
7 - gastric pits in the
mucosa
8 - muscularis mucosae
26. Types of cells present in the stomach
• Mucous secreting cells (goblet
cells)-
– Line the luminal surface of the
stomach and gastric pits and gastric
glands.
– produce mucus and bicarbonate.
•Mucous neck cells-
Present in the neck of the gland.
Produce mucin.
•Parietal cells (oxyntic cells)
Distributed throughout the length of the gland,
but numerous in the middle portion.
Large, rounded cells with eosinophilic cytoplasm
and centrally located nucleus. Produce gastric acid.
27. • Chief cells (peptic or
zymogenic cells)
– Clustered at the base of the
gland.
– Identified by basally located
nuclei and strongly basophilic
granular cytoplasm.
Produce pepsinogen, digests
protein.
28.
29. The Lamina Propria
• Consists of a layer of
areolar tissue that
contains:
– blood vessels
– sensory nerve
endings
– lymphatic vessels
– smooth muscle cells
– scattered areas of
lymphoid tissue