[Intracellular recordings of the multiple innervation of Purkinje cells by climbing fibers in the cerebellum of the developing rat].

Intracellular recordings of postsynaptic potentials evoked in cerebellar Purkinje cells (PCs) by activation of the climbing fibers (CFs) have been obtained from 3 to 15 day-old Rats. The data presented confirm the multiple innervation of PCs by CFs on postnatal days 8-9, and demonstrate its existence at earlier stage (from day 3). The evolution of the precentage of multinnervated PCs and of the mean number of CFs collaterals per PC was followed until the monoinnervation was established on day 15.