Role of hypothalamic neuropeptide Y in feeding and obesity

The 36-amino-acid peptide, neuropeptide Y (NPY), is the most abundant pepti de in the rat brain. When administered into the brain, NPY produces a varie ty of physiological actions including a pronounced stimulation of feeding i n satiated rats. Elevations in hypothalamic NPY have been reported after fo od deprivation and in genetically obese rodents. NPY is believed to produce its actions through a portfolio of G-protein coupled receptors, Y1, Y2, Y4 and Y5. Studies using peptide analogs, receptor knockout animals and speci fic receptor antagonists suggest the Y1 and Y5 receptors are important in m ediating the effects of NPY on food intake in rats. Development of specific receptor antagonists with improved pharmacokinetic properties will be requ ired to determine the importance of NPY in human obesity and appetite disor ders. (C) 1999 Harcourt Publishers Ltd.