GI Physiology Revision

Question 1

Where are Parietal cell located & what do they secrete?

Answer 1

Located in the body of the stomach & secrete Gastric acid

Question 2

Where are G-cells located & what do they secrete?

Answer 2

Located in antral part of the stomach, secrete gastrin which stimulates parietal cells, EC cells & D-cell secretion.

Question 3

What do EC-like cells secrete?

Answer 3

Histamine which acts via H2 receptors on parietal cells to promote acid secretion

Question 4

What do D-cell secrete?

Answer 4

Somatostatin which inhibits Parietal, G & EC-Like cells

Question 5

What do Chief cells secrete?

Answer 5

Pepsinogen & renin

Question 6

What neurotransmitter acts on …. receptors on …. (3) cells

Answer 6

Acetylcholine acts on muscarininc receptors on parietal, EC-like & D-cells.

Question 7

During the Cephalic phase what nerve mediates acid secretion?

Answer 7

Vagus nerve (CNX)

Question 8

If proton secretion is in excess of what is required in the stomach what happens?

Answer 8

Falling pH inhibits gastrin release by G-cells & stimulates somatostatin release.