The electrophysiological effects of nicotine in the rat cerebellum: evidence for direct postsynaptic actions.

The agonistic actions of nicotine in the cerebellum were dependent on the type of cerebellar neuron studied. Purkinje cells were inhibited and cerebellar interneurons were excited by pressure-ejected nicotine. The simultaneous iontophoresis of Mg2+ failed to block nicotine agonistic actions on either cell type. Since Mg2+ reduces presynaptic release of neurotransmitters, our findings suggest that the pharmacological actions of nicotine on cerebellar neurons are due to direct postsynaptic mechanisms.