Fiser Chapter 28 GUT HORMONES

Question 1

What cells produce:

1. Gastrin
2. Somatostatin
3. CCK
4. Secrein
5. VIP
6. Glucagon
7. Insulin
8. Pancreatic polypeptide
9. Motilin
10. Bombesin

Answer 1

1. Gastrin: antral G cells
2. Somatostain: antral D cells
3. CCK: duodenal I cells
4. Secretin: duodenal S cells
5. VIP: gut and panc
6. Glucagon: pancreas alpha cells
7. Insulin: pancreas beta cells
8. Pancreatic polypeptide: pancreas islet cells
9. Motilin: intestinal cells

Question 2

What stimulates and inhibits gastric release from antral G cells?

Answer 2

Stimulated by: amino acids, vagal input (ACh), Calcium, EtOH, Antral distension, pH > 3.0

Inhibits: pH<3.0, somatostain, secretin, CCK

Question 3

Gastrin does what?

Answer 3

Acts on parietal and chief cells to increase HCL, IF, and pepsinogen activation

Question 4

Omeprazole MoA

Answer 4

Blocks H/K ATPase of parietal cell (final pathway for H+ release)

Question 5

What stimulates somatostatin release from antral D cells?

Answer 5

Acid in duodenum

Question 6

What is the response to somatostatin?

Answer 6

Inhibits gastrin and HCL release

Inhibits release of insulin, glucagon, secretin, motilin

Decreases pancreatic and biliary output

Question 7

What can be used to decrease pancreatic fistula output?

Answer 7

Ocreotide

Question 8

What stimulates CCK release from duodenal I cells?

Answer 8

Amino acids and fatty acid chains

Question 9

What is the response to CCK?

Answer 9

Gallbladder contraction, sphincter of Oddi relaxation, and pancreatic enzyme secretion

Question 10

What stimulates and inhibits secretin release from duodenal S cells?

Answer 10

Stimulated by: fat, bile, pH<4.0

Inhibited by pH>4.0 and gastrin

Question 11

What is the response to secretin?

Answer 11

Pancreatic bicarb release (decreased in chronic pancreatitis and end stage pancreatitis)

Inhibited gastrin release (reversed in gastrinoma)

Inhibited HCL release

Question 12

Pancreatic Secretin Test

Answer 12

Normal 2ml/kg/hr, bicarb >10mmol/L/hr, amylase 6-18 IU/kg

1. Chronic panc: decreased bicarb
2. End stage panc: decreased all
3. Malnutrition: decreased enzyme
   Panc cancer: decreased volume
   Zollinger-Ellision: increased volume

Question 13

What stimulates VIP release?

Answer 13

Fat and ACh

Question 14

What is the response to VIP?

Answer 14

Increased intestinal secretion (water and electrolytes) and motility

Question 15

VIPoma

Answer 15

WDHA: watery diarrhea, hypokalemia, achlorhydria

Question 16

What stimulates and inhibits

Answer 16

Stimulated by: low glucose, high amino acids, ACh

Inhibited by: glucose, insulin, somatostatin

Question 17

Result of glucagon?

Answer 17

Glycogenolysis, gluconeogenesis, lipolysis, ketogenesis, decreased HCL, decreased GI motility, relaxes sphincter of Oddi

Question 18

What stimulates and inhibits insulin?

Answer 18

Stimulated by: glucose, glucagons, CCK

Inhibited by: somatostatin

Question 19

Response to insulin?

Answer 19

Cellular glucose uptake, promotes protein synthesis

Question 20

What stimulates pancreatic polypeptide from panc islet cells?

Answer 20

Food, vagus, hormons

Question 21

Pancreatic polypeptide response?

Answer 21

Decrased pancreatic and gallbladder secretion

Question 22

What stimulates and inhibits motilin release by gut intestinal cells?

Answer 22

Stimulated by: duodenal acid, food, vagus

Inhibited by: somatostatin, secretin, pancreatic polypeptide, duodenal fat

Question 23

Motilin response?

Answer 23

Increased motility (small bowel; phase III peristalsis) –> erythromycin acts here

Question 24

Bombesin

Answer 24

Gastrin-releasing peptide (GRP)

Causes increased intestinal motor activity, increased pancreatic enzyme secretion, and increased gastric acid secretion

Question 25

Peptide YY

Answer 25

Ileal break Released from TI after a fatty meal inhibits acid secretion and stomach contraction Inhibits gallbladder contraction and pancreatic secretion

Question 26

What mediates anorexia?

Answer 26

Hypothalamus

Question 27

Bowel recovery order

Answer 27

Small bowel 24 hours Stomach 48 hours Large bowel 3-5 days

Question 28

Enterokinase

Answer 28

Activates trypsinogen to trypsin -> activates other enzymes of digestion

Question 29

MMC phases

Answer 29

Interdigestive motility; 90 min cycles; starts in stomach, goes to TI I. quiescence II. gallbladder contraction III. peristalsis IV. subsiding electric activity

Question 30

Where is gastrin made?

Answer 30

antrum G cell

Question 31

Where is somatostatin made?

Answer 31

antrum D cell

Question 32

Where is CCK made?

Answer 32

duodenal I cell

Question 33

Where is secretin made?

Answer 33

duodenal S cells

Question 34

Where is VIP made?

Answer 34

Gut and pancreas cells

Question 35

Where is glucagon made?

Answer 35

pancreatic Alpha cells

Question 36

Where is insulin made?

Answer 36

pancreas Beta cells

Question 37

Where is pancreatic polypeptide made?

Answer 37

Panc islet cells

Question 38

Where is motilin made?

Answer 38

Intestinal cells