HCL secretion is stimulated by:

HCL secretion is stimulated by:

A. Secretin
B. Somatostatin
C. Histamine
D. Gastrin
E. VIP


Answer is C and D. C. Histamine D. Gastrin

Gastrin is a hormone which is produced by G-cells in the lateral wall of glands in the gastric antral mucosa.

• It stimulates gastric acid secretion and pepsin secretion.
• Its stimulates growth of the mucosa of stomach, small and large intestine.
• It promotes gastric emptying
• It stimulates insulin secretion
• Any stimuli that influences gastrin secretion indirectly affects acid secretion in the stomach.

Stimuli that promote gastrin secretion are:

• Luminal: Peptides and amino acids, distension
• Blood borne: Calcium, Epinephrine
• Neural: Increased vagal discharge via Gastrin releasing polypeptide (GRP) which is noncholinergic.

Stimuli that inhibit gastrin secretion are:

• Luminal: Acid, Somatostatin
• Blood borne: Secretin, GIP, VIP, Glucagon, Calcitoni

- Total acid secretion depends on the functional parietal cell mass.
- Acid secretion is stimulated by Histamine via H2 receptor and Acetylcholine via M3 receptors
- H2 blockers like ranitidine decrease gastric secretion but proton pump inhibitors like pantoprazole blocks gastric acid secretion.