Page 561 - Atlas of Histology with Functional Correlations

SECTION 2 Stomach

The stomach is an expanded hollow organ situated between the esophagus and

the small intestine. At the abrupt transition esophageal–stomach junction, the
simple columnar epithelium of the stomach is lined by cells that produce a
large quantity of mucus. The mucus adheres to the surface epithelium and
protects the stomach lining from the corrosive gastric juices of the gastric glands.

The stomach cardia is where the esophagus terminates. The upper dome-

shaped portion is the fundus, below which is located the body or corpus of the
stomach. The funnel-shaped, lower terminal region of the stomach is the
pylorus. The fundus and the body compose about two thirds of the stomach,
have identical histology, and form the major portions of the stomach. As a result,

the stomach has three distinct histologic regions: cardiac, fundus/body, and
pylorus. Also, all stomach regions exhibit rugae, the longitudinal folds of the
mucosa and submucosa that are temporary, but disappear when the stomach is
distended with fluid or solid material.

The luminal surface of the stomach is pitted with numerous tiny openings

called gastric pits (Fig. 14.9). These pits are formed by the luminal epithelium
that invaginates the underlying lamina propria of the mucosa. The gastric
glands are located below the surface (luminal) epithelium and open directly into

the gastric pits that deliver their secretions into the stomach lumen. The gastric
glands descend through the lamina propria to the muscularis mucosae. The
stomach mucosa consists of different cell types and deep gastric glands that
produce most of the gastric secretions or juices for digestion.

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