ABSITE Review - GI Hormones

Question 1

Mention the cells that produce the following hormones.

Answer 1

Mention the cells that produce the following hormones.

Question 2

Gastrin

Answer 2

G cells in antrum

Question 3

Somatostatin

Answer 3

D cells in antrum

Question 4

Gastric inhibitory peptide (GIP)

Answer 4

K cells in duodenum

Question 5

CCK

Answer 5

I cells of duodenum and jejunum

Question 6

Secretin

Answer 6

S cells of duodenum

Question 7

Insulin

Answer 7

Beta-cells of the pancreas

Question 8

Glucagon

Answer 8

Alpha-cells of the pancreas

Question 9

Pancreatic polypeptide

Answer 9

Islet cells in pancreas

Question 10

Motilin

Answer 10

Intestinal cells of gut

Question 11

What stimulates the secretion of GASTRIN?

Answer 11

AAs, vagal input (Ach), Ca, ETOH, antral distention, pH >3.0

Question 12

What inhibits the secretion of GASTRIN?

Answer 12

pH < 3.0, somatostatin, secretin, CCK, VIP, GIP

Question 13

What are the target cells of GASTRIN? What is the response?

Answer 13

Target cells - parietal cells and chief cells

Response - increase HCl, IF and pepsinogen secretion

Question 14

What stimulates the secretion of SOMATOSTATIN?

Answer 14

Acid in the duodenum

Question 15

What are the target cells of SOMATOSTATIN? What is the response?

Answer 15

Target cells - many; it is the great inhibitor
Response - inhibits gastrin and HCl release; inhibits release of insulin, glucagons, secretin, GIP, motilin, neurotensin, enteroglucagon; decrease pancreatic and biliary outoput

Question 16

What stimulates the secretion of GIP?

Answer 16

AAs, glucose, long-chain FAs, decrease pH

Question 17

What are the target cells of GIP? What is the response?

Answer 17

Target cells - parietal cells of the stomach and beta cells of the pancreas
Response - decrease HCl secretion and pepsin; increase insulin release

Question 18

What stimulates the secretion of CCK?

Answer 18

AAs, fatty acids chains

Question 19

What are the response to CCK?

Answer 19

Response - GB contraction, relaxation of sphincter of Oddi, increase pancreatic enzyme secretion, some increase intestinal motility

Question 20

What stimulates the secretion of SECRETIN?

Answer 20

Fat, bile, pH < 4.0

Question 21

What inhibits the secretion of SECRETIN?

Answer 21

pH > 4.0, gastrin

Question 22

What are the responses to SECRETIN?

Answer 22

Response - increase pancreatic bicarbonate release, increase bile flow, inhibits gastrin release (this is reverse on patients with gastrinoma) and inhibits HCl release

Question 23

How varies the composition of a high vs slow pancreatic duct output?

Answer 23

High pancreatic duct output - increase HCO3, decrease Cl

Slow pancreatic duct output - increase Cl, decrease HCO3 (carbonic anhydrase in duct exchange HCO3 for Cl)

Question 24

What stimulates the secretion of VIP?

Answer 24

Fat, ACh

Question 25

What are the response to VIP?

Answer 25

Response - increase intestinal secretion (water and electrolytes) and motility. Inhibits gastrin release.

Question 26

What stimulates the secretion of INSULIN?

Answer 26

Glucose, glucagons, CCK

Question 27

What inhibits the secretion of INSULIN?

Answer 27

Somatostatin, pancreatostatin

Question 28

What are the responses to INSULIN?

Answer 28

Response - cellular glucose uptake; promotes protein synthesis

Question 29

What stimulates the secretion of GLUCAGON?

Answer 29

Decrease glucose, increase AAs, ACh, gastrin releasing peptide

Question 30

What inhibits the secretion of GLUCAGON?

Answer 30

Increase glucose, increase insulin, somatostatin

Question 31

What are the responses to GLUCAGON?

Answer 31

Response - glycogenolysis, gluconeogenesis, lipolysis, ketogenesis, decrease gastric acid secretion, decrease pancreatic secretion, decrease intestinal motility, decrease stomach motility, increase LES pressure, decrease MMCs

Question 32

What stimulates the secretion of Pancreatic Polypeptide?

Answer 32

Food, vagal stimulation, other GI hormones

Question 33

What are the response to Pancreatic polypeptide?

Answer 33

Response - decrease pancreatic and gallbladder secretion

Question 34

What stimulates the secretion of MOTILIN?

Answer 34

Duodenal acid, food, vagus input, gastrin-releasing peptide

Question 35

What inhibits the secretion of MOTILIN?

Answer 35

Somatostatin, secretin, pancreatic polypeptide, duodenal fat

Question 36

What are the responses to MOTILIN?

Answer 36

Response - increase intestinal (small bowel) motility --> erythromycin acts on this receptor

Question 37

What are the responses to Bombesin (gastric releasing peptide)?

Answer 37

Increase intestinal motor activity, increase pancreatic enzyme secretion, increase gastric acid secretion

Question 38

What are the responses to peptide YY?

Answer 38

Inhibits acid secretion and stomach contraction; inhibits gallbladder contraction and pancreatic secretion

Question 39

What is the usual recovery time of small bowel?

Answer 39

24 hours

Question 40

What is the usual recovery time of stomach?

Answer 40

48 hours

Question 41

What is the usual recovery time of colon?

Answer 41

3-5 days