[The excitatory effects of histamine on cerebellar cortical Purkinje cells in the rat].

The effects of histamine on Purkinje cells (PCs) in lobule X of cerebellar cortex were investigated in rat cerebellar slices. Histamine elicited PCs' responses predominately excitatory (94.4%, 51/54), only few inhibitory (5.6%, 3/54). The excitatory response could not be abolished by perfusing the slices with low Ca2+/high Mg2+ medium. The excitatory response of PCs to histamine could be blocked by histamine H2 receptor antagonist ranitidine, but not by H1 receptor antagonist triprolidine readily. These results suggest that histamine exerts an excitatory effect on the PCs via H2 receptors. Presumably, hypothalamo-cerebellar histaminergic fibers participate in the regulation of somatic and non-somatic functions of the cerebellum.