Characterization of neuropeptide Y (NPY) receptors in human hippocampus

Abstract

We identified a 50 kDa neuropeptide Y (NPY) receptor from human hippocampus by affinity labeling. NPY specific binding and labeling of the receptor were inhibited in parallel by increasing concentrations of unlabeled NPY (IC= 0.27nM and0.18nM, respectively). Peptide YY (PYY), but none of the pancreatic polypeptides, was as effective as NPY in displacing [ 125I]NPY. NPY fragments inhibited binding with the rank order of potency: NPY>NPY 13–36 >NPY 20–36≥NPY 18–36 >NPY 1–36free acid≥NPY 26–36. These results demonstrate that the human hippocampal NPY receptor is a 50 kDa protein fitting the classification of a Y 2 receptor subtype.