Types of Secretory Epithelial Cells
Four major types of secretory epithelial cells
cover the surface of the stomach and extend down into gastric pits and glands:
- Mucous cells: secrete an alkaline mucus that protects the epithelium against shear stress and acid.
- Parietal cells: secrete hydrochloric acid!
- Chief cells: secrete pepsin, a proteolytic enzyme.
- G cells: secrete the hormone gastrin.
There are differences in the distribution of these cell
types among regions of the stomach - for example, parietal cells are abundant in the glands of the body, but virtually absent in pyloric glands. The micrograph above shows a gastric pit invaginating into the mucosa (fundic region of a raccoon stomach). Notice that all the surface cells and the cells in the neck of the pit are foamy in appearance - these are the mucous cells. The other cell types are farther down in the pit and, in this image, difficult to distinguish.NEXT > Gastric MotilitySource:
Republished with permission by Richard Bowen - Hypertexts for Biomedical Sciences