The expression of neuronal voltage-dependent calcium channels in human cerebellum

Little is known about the comparative distribution of voltage-dependent calcium channel subtypes in normal human brain. Previous studies in experimental animals have predominantly focused on the regional expression of single alpha(1) genes. We describe the preparation of riboprobes and antisera specific for human alpha(1A), alpha(1B) and alpha(1E), subunits and their application in comprehensive mapping studies of the human cerebellum. Within the cerebellar cortex, these pore forming proteins were found to have differential localisations when examined in adjacent sections. The alpha(1A), and alpha(1B) subunits broadly colocalised and were both present, though at apparently different levels, in the molecular, Purkinje and granule cell layers whilst alpha(1E) was predominantly expressed in Purkinje cells. In the dentate nucleus, an area which has received little attention in previous studies, alpha(1A) was highly expressed in regions in which Purkinje cell nerve terminals form synapses with deep cerebellar neurones.