Development of the cerebellar cortical efferent projection: an in-vitro anterograde tracing study in rat brain slices.

This study reports the results of an anterograde HRP analysis of the development of cerebellar cortical efferents studied in-vitro with cerebellum-brainstem slices from embryonic (E-18) through newborn rats. From E-18, Purkinje cells in the medial region of the cerebellum are seen to project to the medial cerebellar and vestibular nuclei, their appropriate targets in the adult animal. Thus, the cortical efferent system is forming during late embryogenesis and may establish synaptic contacts with target cells as early as E-20.