Beta-adrenergic receptors in rat cerebellum after neonatal X-irradiation: effect of prolonged imipramine and lithium treatment.

The actions of prolonged treatment of rats within imipramine or lithium chloride on the beta-adrenergic cAMP generating system of the cerebellum were compared in normal animals and in rats degranulated by neonatal X-irradiation. Whereas in normal animals imipramine treatment is without significant effect on the cerebellar cAMP system but lowers the beta-adrenoceptor density significantly, in degranulated animals the cAMP system becomes subsensitive towards norepinephrine after prolonged imipramine treatment. These data support the hypothesis that in the cerebellum imipramine acts predominantly on beta-adrenoceptors located particularly on Purkinje cells. Prolonged lithium treatment exhibited no significant effects on beta-receptors nor the noradrenergic cAMP generating system of normal and degranulated cerebella.