GI physiology: Intro and GI hormones Flashcards
1
Q
What are the 3 criteria for required to be a hormone?
A
- Secreted in response to a physiologic stimuli into the blood to act at a distant site.
- Independent of neural activity
- Must be isolated and chemically identified.
2
Q
What molecular difference differentiates the activity of Gastrin and CCK?
A
Gastrin has a Tyr at the 6th position from the C-term. CCK has a Tyr at the 7th position from the C-term.
3
Q
What is the difference between G17 and G34?
A
G17 is little gastrin which in secreted at high levels in response to meals. G34 is big gastrin which is secreted at low levels in between meals.
4
Q
What specifically does gastrin require for activity?
A
It requires its first 4 aa.
5
Q
What is the difference between CCKA and CCKB receptors?
A
CCKA receptor is selective for CCK. CCKB receptor is sensitive to both CCK and gastrin.
6
Q
What hormones belong to the secretin-glucagon family?
A
Secretin
Glucagon
VIP
GIP
