Neuropeptide Y (NPY) is a 36 amino acid peptide neurotransmitter present in the central and peripheral nervous systems.NPY is involved in the regulation of a broad range of functions such as eating behavior, hypertension, and reproduction.NPY5R as well as NPY1R and NPY2R are expressed in the hypothalamus, in the brain stem, and in peripheral tissues, such as blood vessels, lung, kidney, adrenal glands, stomach, colon, heart, pancreas, and intestine. NPY5R has been postulated as the mediator of the feeding response to NPY and related peptides (125 in Kamiji, M. M). Its localization in the brain is consistent with this hypothesis