Rotation induced by intranigral phenobarbital: evidence of barbiturate GABAergic activity.

Abstract Phenobarbital, injected unilaterally into the pars reticulata of the substantia nigra, induced significant contraversive rotation. Similar to the rotation induced by intranigral administration of GABA agonists, phenobarbital-induced rotation was antagonized by prictoxin and persisted in animals with 6-hydroxydopamine-induced denervation of the ipsilateral nigrostriatal dopamine system. The results of this study support the hypothesis that the antoconvulsant barbiturates enhance central GABA-mediated events.