Mucosal Cell Types and Gastric Glands: The Dynamic Duo

Cell Bio Lecture 4

Mucus surface cell

Secretes mucus

Mucous neck cell

Secretes bicarbonate

Parietal Cells

Secrete gastric acid (HCl) and intrinsic factor

Enterochromaffin-like cells

Secretes histamine

Chief cells

Secretes pepsinogen and gastric lipase

D cells

Secretes somatostatin

G cells

Secretes gastrin

Function of Mucus

Physical barrier between lumen and epithelium

Function of bicarbonate

Buffers gastric acid to prevent damage to the epithelium

Function of gastric acid

Activates pepsin; kills bacteria

Function of Intrinsic factor

Complexes with vitamin B12 to permit absorption

Function of histamine

Stimulates gastric acid secretion

Function of pepsin(ogen)

Digests proteins (only as pepsin)

Function of gastric lipase

Digests fats

Function of Somatostatin

Inhibits gastric acid secretion

Function of gastrin

Stimulates gastric acid secretion

Stimulus for release of mucus

Tonic secretion (secreted at baseline); irritation of mucosa

Stimulus for release of bicarbonate

Secreted with mucus

Stimulus for release of gastric acid and intrinsic factor

Acetylcholine, gastrin, histamine

Stimulus for release of histamine

Acetylcholine, gastrin

Stimulus for release of pepsin(ogen) and gastric lipase

Acetylcholine, acid secretion

Stimulus for release of somatostatin

Acid in the stomach

Stimulus for release of gastrin

Acetylcholine, peptides, and amino acids

Where are oxyntic glands located?

In the body of the stomach

Where are pyloric glands located?

In the antrum of the stomach

Which glands are only oxyntic?

Parietal

What is the only essential secretion in the stomach?

Intrinsic factor

Where are peptic cells located?

In the body of the stomach

What is another name for peptic cells?

Chief cells

Which cells are only pyloric?

G cells

Which cells have secretions common to both oxyntic and pyloric glands?

Enterochromaffin (ECL), D cells, and mucosa