Peptide YY

Pancreatic Peptide YY3-36 is a peptide produced in the small intestine and colon that reduces appetite in response to feeding.

Description
Peptide YY3-36 (PYY) is a linear polypeptide consisting of 36 amino acids with structural homology to NPY and pancreatic polypeptide. PYY exerts its action through neuropeptide Y receptors, inhibits gastric motility and increases water and electrolyte absorption in the colon. It is secreted by the gut in response to a meal, and has been shown to reduce appetite.

Relevance to obesity
Leptin also reduces appetite in response to feeding, but obese people develop a resistence to leptin. In contrast, obese people secrete less PYY than normal people do, and in response to added PYY, they reduce their food intake.