Inhibition of in vivo 3H-spiperone binding by the proposed antipsychotic Des-Tyr1-gamma-endorphin.

The proposed antipsychotic neuropeptide des-tyrosine1-gamma-endorphin (DT gamma E, beta LPH62,77) inhibits in vivo 3H-spiperone binding in the hypothalamus, corpus striatum and mesolimbic areas of rat brain. The neuroleptic drug haloperidol produces similar effects in these areas as well as in frontal cortex, but is considerably more potent than DT gamma E. Correspondingly, haloperidol produces postural and motor abnormalities not seen with DY gamma E. These data together with the results from previous in vitro studies suggest DT gamma E might act indirectly, having a selective neuroleptic-like action at 3H-spiperone binding sites.