Method for isolation of kappa-opioid binding sites by dynorphin affinity chromatography

Abstract
A kappa‐opioid receptor subtype was purified from a digitonin extract of frog brain membranes, using affinity chromatography. The affinity resin was prepared by coupling dynorphin (1–10) to AH Sepharose 4B. The purified receptor binds 4,750 pmol [3H]ethylketocyclazocine (EKC) per mg protein (5,600‐fold purification over the membrane‐bound receptor) with a Kd of 9.1 nM. The addition of cholesterol‐phosphatidylethanolamine (2:1) enhanced 3.6‐fold the binding activity of the purified material, which gives a purification very close to the theoretical. The purified receptor protein exhibits high affinity for kappa‐selective ligands. The purified fraction shows one major band (65,000 Mr) in sodium dodecyl sulfate (SDS) gel electrophoresis.

This publication has 27 references indexed in Scilit: