Cytochrome P450 17α-hydroxylase/C(17,20)-lyase immunoreactivity and molecular expression in the cerebellar nuclei of adult male rats

Abstract Several probes have been developed to identify steroidogenic activity in the brain of vertebrates. However, the presence of the cytochrome P450 17α-hydroxylase/C(17,20)-lyase (P450C 17 ), an enzyme that converts pregnenolone and progesterone into dehydroepiandrosterone and androstenedione, in specific areas of the cerebellum such as the deep cerebellar nuclei, remains virtually unexplored. Using Western blot analysis and immunohistochemistry, we found molecular expression of P450C 17 in the lateral, interposed and medial deep cerebellar nuclei. Moreover, double immunofluorescence procedures enabled localization of P450C 17 mainly in neurons, axons and glutamatergic synapses. Taken together, these data demonstrate the occurrence of P450C 17 in the deep cerebellar nuclei, and enable the chemical characterization of the cells that express the cytochrome.