The gastric mucosa is covered in surface mucous cells that produce the mucus necessary to protect the stomach's epithelial lining from gastric acid secreted by parietal cells in the glands, and from pepsin, a secreted digestive enzyme.

Surface mucous cells follow the indentations and partly line the gastric pits.

[1] Mucus lines the entire stomach as gastric mucosa protecting the stomach lining from the effects of hydrochloric acid produced by the parietal cells and released from the oxyntic glands.

[5][6] Gastric juice contains water, hydrochloric acid, intrinsic factor, pepsinogen, and salts.

[5] The composition of the fluid varies according to the time of eating, and the rates of activity of the various cells.

There are two kinds - either simple tubular with short ducts or compound racemose resembling the duodenal Brunner's glands.

Oxyntic means acid-secreting and they secrete hydrochloric acid (HCl) and intrinsic factor.

These cells almost fill the tube and the remaining lumen is continued as a very fine channel.

Pernicious anemia is caused when damaged parietal cells fail to produce the intrinsic factor necessary for the absorption of vitamin B12.

List of distinct cell types in the adult human body This article incorporates text in the public domain from the 20th edition of Gray's Anatomy (1918)