Prostaglandins, cyclic AMP and the biochemical mechanism of opiate agonist action.

The paper re-examines, in the light of recent evidence, the original proposition that the ability of opiates to inhibit the stimulation by E prostaglandins of cyclic AMP formation in rat brain homogenate represents a biochemical mechanism that could account for the analgesic and allied effects of these drugs. It is concluded that subsequent evidence largely supports the original proposition; but that this can now be made more definite. It is proposed that inhibition of an adenylate cyclase of morphine-sensitive neurones is the decisive biochemical consequence of the binding of an opiate agonist with its specific receptor.