cDNA cloning and pharmacological characterization of an opioid receptor with high affinities for κ‐subtype‐selective ligands

Abstract

The amino acid sequence of a rat opioid receptor, designated as ROR-D, has been deduced by cloning and sequencing the cDNA. The ROR-D expressed from the cDNA exhibits high affinities for ligands selective for the opioid receptor kappa-subtype and low affinities for ligands selective for the delta- and mu-subtypes. RNA blot hybridization analysis indicated that ROR-D mRNA is distributed in cerebrum and brainstem but not in cerebellum.