Autoradiographic localization of drug and neurotransmitter receptors: focus on the opiate receptor.

Receptors for drugs and neurotransmitter can be visualized at the light microscopic level by autoradiography after "in vitro" labelling of slide-mounted tissue sections. This methodology is illustrated by the localization of mu, delta and kappa opiate receptors in the rat, guinea-pig and human brains using the opiate ligand 3H-(--)-bremazocine. The differential anatomical localizations of these sites and their relationship with opiate effects is discussed.