GI Hormones Flashcards
1
Q
What is a consequence of having less H+ present in the stomach?
A
There will be less negative feedback →H+ receptors on D cells won’t get as activated →less somatostatin will be produced →more gastrin will be present in the serum.
2
Q
How do we control the amount of acid secretion?
A
- ACh via Vagus
- Gastrin via G Cells
- Gastrin-> ECL -> Histamine
- D Cells -> Somatostain -> Inhbiits Gastrin
3
Q
- Voluminous diarrhea
- Hypokalemia
- AChlorhydria
A
VIPoma/WDHA Syndrome -> Tx Octeotride
4
Q
GLP-1/GIP
A
- Produced by K Cells in Duodenum + Jejunum
- stimulated by FAs, AA, + Oral glucose
- Stimulates insulin, DEC H+ secretions
5
Q
What causes higher insulin levels in Oral vs IV glucose?
A
GIP
6
Q
Guanylin
A
- secreted by goblet cells in colon
- INC cGMP -> Chloride secretion + Diarrhea
- Same mechanism as heat-stable enterotoxins
7
Q
Soimatostatin vs Secretin
A
Somatostatin: Paracrine; inhibit Gastrin;
Secretin: Hormone; inhibit gastrin; stimulate HCO3 secretion
8
Q
What is CCKs affect on the stomach?
A
DEC gastric emptying
9
Q
Where is Gastrin secreted?
A
Portal vein circulation
