Regulation of Secretion of HCL

Question 1

The parietal cells are stimulated and the transport of H+ into the lumen is active and mediated by H+, K+ ATPase. Carbonic anhydrase catalyzes the production of ____.

Answer 1

HCO3- which is exchanged for Cl-

For every H+ secreted int the lumen (which becomes acid), a bicarb is secreted into the blood plasma (becomes alkaline)

Question 2

In the duodenum, ____ is secreted in response to neurocrines GRP and ACh and by hydrolyzed PROTEIN (amino acids).

Answer 2

Gastrin (CCK-B)

Question 3

In the Gastric antrum, ____ inhibits acid secretion by both paracrine and hormonal mechanisms by binding to receptors on parietal and ECL cells.

Answer 3

somatostatin

Question 4

___ is the stimulus in the gastric antrum that inhibits G cell secretion of Gastrin and stimulates secretion of SST by the D cell.

Answer 4

pH less than 3

Question 5

_____ is stimulated when the pH of the duodenum is less than 4.5

Answer 5

secretin and enterogastric reflex

Question 6

_____ is stimulated by fatty acids, glucose, and amino acids in the duodenum and jejunum.

Answer 6

GIP and CCK

Question 7

What are some inhibitors of HCL secretion?

Answer 7

Secretin
CCK
GIP
Prostaglandin E2

Question 8

___ inhibits secretion of gastrin, stimulates secretion of SST, and down regulates acid secretion mechanisms in parietal cells.

Answer 8

secretin