Regulation of GI function

Question 1

what hormone is released in response to high levels of fatty chyme & AAs in the duododenum?

Answer 1

cholecystokinin (CCK)

Question 2

what hormone is released in response to high levels of acid in the duodenum?

Answer 2

secretin

Question 3

functions of secretin

Answer 3

1. release of bicarbonate from Brunner’s glands
2. release of pancreatic fluid
3. increase liver ductal secretion
4. decrease gastric emptying
5. inhibit motility

Question 4

what hormone is released in response to increased glucose in the duodenum?

Answer 4

GIP: gastric inhibitory peptide
aka Glucose-dependent insulinotropic peptide (GDIP)

Question 5

functions of GIP/GDIP

Answer 5

1. stimulate ^insulin release with oral glucose load compared to IV glucose load
2. inhibit motility by delaying gastric emptying

Question 6

what hormone is released in response to stretch in the stomach?

Answer 6

gastrin

Question 7

functions of gastrin

Answer 7

1. secretion of acid from gastric cells
2. increase motility
3. stimulate growth of gastric mucosa

Question 8

what hormone is released in response to activation of the Myenteric (Auerbach’s) plexus?

Answer 8

VIP: vasoactive intestinal peptide

Question 9

functions of VIP

Answer 9

1. relax sphincters
2. dilate BVs
3. inhibit gastric acid secretion
4. increase motility

Question 10

what hormone is released cyclically between meals?

Answer 10

motilin

Question 11

functions of motilin

Answer 11

1. mediate migratory motor complexes (MMCs)
2. move undigested food toward colon (90mins from stomach to colon)