Purification of the Opiate Receptor from Rat Brain

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 78; no. 1; pp. 636 - 639
• Main Authors: Bidlack, Jean M., Abood, Leo G., Osei-Gyimah, Peter, Archer, Sydney
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences of the United States of America 01.01.1981; National Acad Sciences
• Subjects: Animals; Brain Chemistry; Cell Membrane - analysis; Chromatography, Affinity; Dihydromorphine - metabolism; Electrophoresis; Electrophoresis, Polyacrylamide Gel; Elution; Etorphine - metabolism; Gels; Levorphanol - metabolism; Ligands; Molecular weight; Morphine Derivatives - metabolism; Opiates; Opioid receptors; P branes; Rats; Receptors; Receptors, Opioid - isolation & purification; Receptors, Opioid - metabolism; Solubility; Solubilization
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.78.1.636

The opiate receptor was purified from a Triton-solubilized preparation of rat neural membranes by the use of affinity chromatography. The affinity gel was prepared by coupling 14-β -bromoacetamidomorphine, a newly synthesized ligand, to ω -aminohexyl-Sepharose. After elution of the nonspecific proteins with 50 mM Tris (pH 7.5), the receptor proteins were eluted with 1 μ M levorphanol or etorphine. NaDodSo4/polyacrylamide gel electrophoresis revealed three major proteins associated with the opiate receptor, having molecular weights of 43,000, 35,000, and 23,000. The purified receptor binds 10-11mol of dihydromorphine/per mg of protein, with Kdof 3.8× 10-9M. Other opiates, naloxone, and methionine-enkephalin, inhibit [3H] dihydromorphine binding in a manner similar to that observed with intact and solubilized neural membranes.