Opioid receptor proteins in human brain. Detection with monoclonal anti-idiotypic antibodies.

: In order to identify opioid receptor proteins, we first ascertained the presence of mu-receptors in membranes of the human cerebral frontal cortex, using binding studies performed with sufentanil. Sufentanil binding was reversed by naloxone and prevented by an anti-idiotypic opioid receptor-specific antibody. This antibody was bound specifically by proteins (molecular weights of 66 and 68 Kda) detected in frontal cortex membrane preparations by sodium dodecyl sulphate-polyacrylamide-gel electrophoresis in combination with western blot analysis. Binding of the same antibody was achieved in dot blots of homologous cerebral and cerebellar cortex preparations.