Page 578 - Atlas of Histology with Functional Correlations

Muscularis mucosae and submucosa continue with those of stomach layers

STOMACH

Transition from the esophagus to the stomach is abrupt; stratified squamous

to simple columnar epithelium
Consists of cardiac, fundic and body, and pyloric regions
When contracted or empty, temporary rugae are seen in the wall
Fundus and body form the major region and are histologically identical

Receives, stores, mixes, digests, and absorbs some food products to form
liquid chyme
Converts bolus of ingested food into semiliquid mass called chyme
Surface is pitted by gastric pits, which are connected to gastric glands in the

lamina propria
Surface is lined with mucus-secreting, simple columnar epithelium for
protection
Gastric glands produce gastric juices rich in hydrochloric acid and protein-

digesting enzymes
Muscularis externa shows internal oblique, middle circular, and outer
longitudinal muscle layers
Submucosal and myenteric nerve plexuses regulate peristaltic activity

Serosa or visceral peritoneum covers the outer layer of the stomach

Gastric Pits and Cells of Gastric Glands

In the cardia, gastric pits are shallow; in the pylorus, gastric pits are deep;
both produce mucus
In the body and fundus, parietal cells are large, acidophilic, and are in the
upper gland region
Deeper regions of the gastric glands contain chief or zymogen cells

In cardiac and pylorus, epithelium and simple tubular gastric glands produce
mucus
Glands in the pylorus also produce mucus and bacteria-destroying enzyme

lysozyme
Pylorus gland G cells also secrete gastrin that stimulates parietal cells to
produce HCL
Parietal cells in the fundus and body produce hydrochloric acid and gastric

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