10 Regulation of Food Intake Flashcards
What are the distinct populations within the arcuate nucleus
POMC/CART (anorexigenic)
Neuropeptide Y/AgRP (orexigenic)
What stimulates the POMC and inhibits NPY-AGRP pathway? What is the result?
Leptin; decreased food intake
POMC neurons suppress appetite with _________
α melanocyte stimulating hormone (α-MSH)
What does ghrelin activate
AGRP-NPY neurons to stimulate food intake
Orexigenic effects are mediated through __ receptors of ____
Y1; NPY
AGRP and NPY _______________ and ___________, causing weight gain
Stimulate food intake; decrease energy expenditure
Mutations in what gene have been seen to cause obesity
α MSH receptor = MC4R and MC3R
What is the vagus n role in satiety and feeding
It coordinates the physiology of eating
What does ghrelin do?
- stimulates appetite through NPY secreting neurons
- increases GH secretion
What produces leptin
Fat cells
What does leptin do
Suppresses ghrelin
Stimulation of leptin receptors initiates what
- decreased production of NPY and AGRP
- activation of POMC neurons causing a release of αMSH
- increased production of corticotropin-releasing hormone (decreases food intake)
- increased sympathetic activity (increases metabolic rate and energy expenditure)
- decreased insulin secretion
Insulin can bind to the ________ where it helps to control food intake
Hypothalamus
What does CCK do
- gallbladder contraction
- gut motility
- gastric emptying
- decrease acid
What does PPY do
Peptide that increases while feeding causing decreased apetite
What does oxyntomodulin do
Produced from proglucagon gene and released during meals
Reduces motility and secretion
What does GLP1 do
Released from L cells of SI
Potent inducer of glucose dependent insulin release
What are the options for bariatric surgery
Gastric band
Gastric bypass
Duodenal switch (sleeve + SI bypass)
Sleeve gastrectomy
After RYGB surgery what are suppressed in obese patients
PYY and GLP1
