Agouti Related Protein (AGRP)

Agouti-related protein is a neuropeptide produced in the brain (in the arcuate nucleus of the hypothalamus) by the AgRP/NPY neuron that increases appetite and decreases metabolism and energy expenditure. It is one of the most potent and long-lasting of appetite stimulators. Understanding the role AgRP plays in weight gain may assist in developing pharmaceutical models for treating obesity. It was identified independently by two teams based on sequence similarity with Agouti signalling peptide, a protein synthetized in the skin that controls coat color.The appetite stimulating effects of AgRP are inhibited by the hormone leptin. Adipocytes secrete leptin in response to food intake. This hormone acts in the arcuate nucleus and inhibits the AgRP/NPY neuron from releasing orexigenic peptides.