Cellular site of opiate dependence.

Experiments on whole animals, guinea pig isolated ileum, individual neurones in situ and cultured neuroblastoma--glioma hybrid cells indicate that opiate dependence and associated tolerance develop within neurones bearing specific opiate receptors (opiate-sensitive neurones). The essential change appears to be an hypertrophy of the cyclic AMP system, in response to inhibition by opiate of a neuronal adenylate cyclase.