1. Tunica mucosa: The glandular region of the stomach has permanent elevations called gastric areas, with invaginations called gastric pits (arrow). Gastric glands open into gastric pits.
Lamina epithelialis: Simple columnar epithelium
Lamina propria: Densely packed gastric glands with connective tissue fibers (Fig.1, LP). Fundic glands are straight, branched, tubular glands (Fig. 1, oval) with the following cell types.
a)
Mucous neck cells: Typical mucous cells that occupy the neck of the gland. Intensely PAS +ve.
b)
Chief Cells: Cuboidal or pyramidal cells with spherical nucleus in the basal portion. The area between the nucleus and the free surface contains zymogen granules, which secrete pepsinogen (Fig. 2 &4).
c)
Parietal cells: Large eosinophilic cells wedged between both chief cells and mucous neck cells. Responsible for the production of HCl.
d)
Endocrine cells: Responsible for the production of gastrointestinal hormones.
Lamina muscularis mucosae: Comprised of 2-3 smooth muscle layers (Fig. 1, LMM).
2. Tunica Submucosa: Network of connective tissue fibers with blood vessels, nerves and lymphatics (TS).3. Tunica Muscularis: Comprised of inner oblique, middle circular and outer longitudinal layers.4. Tunica Serosa: Connective tissue lined by mesothelium
