PRETREATMENT WITH A DOPAMINE D-1-RECEPTOR ANTAGONIST PREVENTS METABOLIC-ACTIVATION BY COCAINE

The pharmacological mechanism underlying metabolic activation of the r at extrapyramidal system by acute cocaine was examined using the quant itative 2-deoxyglucose autoradiographic method. Pretreatment with a se lective dopamine D-1-like receptor antagonist, SCH 23390, prevented co caine-induced metabolic activation in the entopeduncular nucleus and s ubstantia nigra pars reticulata in a dose-dependent manner. These resu lts suggest that activity in striatonigral circuits is induced by stim ulation of D-1-like receptors by dopamine in the presence of acute coc aine.