Transient expression of choline acetyltransferase-like immunoreactivity in Purkinje cells of the developing rat cerebellum.

The expression of choline acetyltransferase (ChAT)-like immunoreactivity was studied immunohistochemically in the cerebelli of developing rats. Brains were examined from the day of birth (postnatal day 1: P1) until adulthood. From P4 through P21, several Purkinje cells in the uvula, nodule, and flocculus of the cerebellum demonstrated ChAT-like immunoreactivity. After P23, no ChAT-positive neurons were observed in any region of the cerebellum. This finding paralleled the transient expression of acetylcholinesterase in Purkinje cells of these same cerebellar areas during development.