Regarding acid secretion in the stomach

Which of these statements are correct regarding acid secretion in the stomach?

A. Gastrin increases acid secretion
B. Secretin decreases acid secretion
C. H2 blockers decrease acid secretion
D. Total acid secretion reflects functional parietal cell mass
E. Somatostatin increases acid secretion


Answer is A, B, C and D.
A. Gastrin increases acid secretion.
B. Secretin decreases acid secretion.
C. H2 blockers decrease acid secretion.
D. Total acid secretion reflects functional parietal cell mass.

There are three regulatory molecules that stimulate acid secretion (acetylcholine, histamine, gastrin) and one regulatory molecule that inhibits acid secretion (somatostatin).

• Acetylcholine is a neurotransmitter that is released by enteric neurons.
• Histamine is a paracrine that is released from ECL (enterochromaffin-like) cells.
• Gastrin is a hormone that is released by G cells, endocrine cells that are located in the gastric epithelium.
• Somatostatin is also secreted by endocrine cells of the gastric epithelium; it can act as either a paracrine or a hormone.

Hence, somatostatin is the only regulatory molecule that inhibits acid secretion and refutes the last statement.

Regulation of acid control is described in more detail at http://courses.washington.edu/conj/bess/acid/acidreg.html