Appetite Control

Question 1

Where is the appetite control center located?

Answer 1

• in the arcuate nucleus of the hypothalamus

Question 2

What are the two parts of the arcuate nucleus?

Answer 2

• the NPY/AgRP component; orexigenic

- the POMC/CART component; anorexigenic

Question 3

What does NPY/AgRP secrete? What about POMC/CART?

Answer 3

• NPY/AgRP secretes neuropeptide Y (NPY); orexigenic

- POMC/CART secretes melanocortine; anorexigenic

Question 4

What does neuropeptide Y act on? What about melanocortine?

Answer 4

• neuropeptide Y (NPY) acts on the lateral hypothalamic area (LHA); orexigenic
• melanocortine acts on the paraventricular nucleus (PVN); anorexigenic

Question 5

The orexigenic component of the arcuate nucleus is ________; it secretes ________, which activates _______ and inhibits _______. The anorexigenic component of the arcuate nucleus is ________; it secretes ________, which activates _______ and inhibits _______.

Answer 5

• orexigenic: NPY/AgRP; secretes neuropeptide Y (NPY) that activates the lateral hypothalamic area (LHA) and inhibits the paraventricular nucleus (PVN)
• anorexigenic: POMC/CART; secretes melanocortine that activates the PVN and inhibits the LHA

Question 6

Which three hormones are mainly responsible for regulating the appetite control center?

Answer 6

• leptin (anorexigenic), ghrelin (orexigenic), and insulin (anorexigenic)

Question 7

Leptin

Answer 7

• a major anorexigenic hormone; the long-term regulator of appetite
• stimulates POMC/CART and inhibits NPY/AgRP
• leptin is stored and secreted by adipocytes

Question 8

Ghrelin

Answer 8

• a major orexigenic hormone; the short-term regulator of appetite
• stimulates NPY/AgRP
• secreted by the stomach when empty

Question 9

Insulin

Answer 9

• a major anorexigenic hormone; involved in both long and short term control
• stimulates POMC/CART and inhibits NPY/AgRP
• released when there is an abundance of resources (high BGL)

Question 10

What additional appetite control center is there? Where is it located? How does it function?

Answer 10

• the nucleus tractus solitorius (NTS) AKA the satiety center
• located in the brain stem
• it is anorexigenic, providing short-term regulation of hunger