GI Hormones and Appetite Control

Question 1

The peptide hormones produced in endocrine cells of the GI tract and adipose tissue mainly influence what center in the brain

Answer 1

appetite center

Question 2

What are the three main hypothalamic neurotransmitters and neurohormones involved in appetite regulation and what are their functions

Answer 2

NPY: stimulate appetite
Orexin: stimulate appetite and promote wakefulness
MSH: reduce appetite

Question 3

What are the 5 peptide hormones produced outside the hypothalamus that influence appetite and what are their functions

Answer 3

CCK: inhibits appetite center prior to digestion of food
PYY: inhibits NPY secreting neurons in hypothalamus
GLP-2 reduce appetite
Insulin: reduces appetite
Ghrelin: potent appetite stimulator

Question 4

How does Ghrelin exhibit such an intense appetite stimulating effect

Answer 4

1. it activates NPY secreting neurons
2. Stimulates GH secretion from the pituitary

Question 5

What is the adipose tissue peptide hormone that affects appetite? by which mechanisms

Answer 5

Leptin: it suppresses appetite due to stimulation of MSH secreting neurons and inhibition of NPY secreting neurons, it also increases metabolic rate/energy utilization due to activation of the SNS

Question 6

True/False: leptin levels correlate with stored energy levels

Answer 6

true

Question 7

What other effect does leptin have outside of appetite suppression?

Answer 7

it promotes angiogenesis