Radio—ligand equibrium binding assay for Neuropeptide—Y receptor / 中国免疫学杂志

The specific binding of~(125)INPY to membranes from mouse cerebral cortex was investigated using equilibrium binding and kinetic assay.The membranes were preparated by different—speed centrifugation.The equilibrium binding of~(125)I—NPY to membranes at 37℃ to equilibrium was by 50 minute and showed sharp optimum at PH7.0—7.4.The bound,which can't inhibited by other related peptides,was inhibited by unlabled NPY spe—cifically(IC50=0.4nmoi/L).The binding sites for~(125)I—NPY were sensitive to treatment with tripsin and thiol reagents.Theequilibrium binding of~(125)I-NPY to cerebral cortex at 37℃ was characterized by a Kd value of 0.30—0.40nmol/L and the receptor densities were 0.40—0.45 pmol/mg protein.