Appetite-regulating hormones (leptin, ghrelin, NPY, AgRP)
Core concept
- Two opposing neuron populations in the arcuate nucleus (median eminence, outside the BBB -> samples blood)
- NPY / AgRP = orexigenic -> hunger
- POMC / CART = anorexigenic -> alpha-MSH -> MC4R in the paraventricular nucleus -> satiety
- Peripheral hormones set the balance between them
- Ghrelin is the only circulating orexigenic hormone
- Everything else on the list (leptin, insulin, PYY, GLP-1, CCK, amylin) is anorexigenic
- Two timescales
- Leptin/insulin = long-term adiposity signal (proportional to fat mass)
- Gut peptides = meal-to-meal signal
3 more sections, plus exam facts
Premium unlocks every note across every specialty, and the full exam fact library behind it.
Get premium access