Abstract: The neuropeptide Y (NPY) receptor was solubilized from rat brain membranes with the zwitterionic detergent 3‐[(3‐cholamidopropyl)‐dimethylammonio]‐1‐propanesulfonate (CHAPS). The binding of 125I‐NPY to CHAPS extracts was protein, time, and temperature dependent. Unlabeled NPY and the related peptides peptide YY (PYY) and pancreatic polypeptide inhibited 125I‐NPY binding to solubilized receptors with relative potencies similar to those seen with membrane‐bound receptors: NPY > PYY ± pancreatic polypeptide. Scatchard analysis of equilibrium binding data showed the CHAPS extracts to contain a single population of binding sites with a KD of 3.6 ± 0.4 nM (mean ± SEM) and a Bmax of 5.0 ± 0.2 pmol/mg of protein. In addition the 125I‐NPY binding to the soluble receptor was not inhibited by guanosine‐5′‐O‐(3‐thiotriphosphate), in contrast to the GTP sensitivity displayed by the membrane‐bound receptor. Gel filtration chromatography using Sepharose 6B revealed a single peak of binding activity corresponding to a Mr of ∼67,000, and sodium dodecyl sulfate‐polyacrylamide gel electrophoresis analysis after chemical cross‐linking revealed a single band at Mr 62,000. After solubilization and gel chromatography a 50‐ to 100‐fold purification of the NPY receptor was obtained.
|Original language||English (US)|
|Number of pages||6|
|Journal||Journal of Neurochemistry|
|State||Published - May 1991|
- Neuropeptide Y
ASJC Scopus subject areas
- Cellular and Molecular Neuroscience