The development of pre- and postsynaptic components of the noradrenergic system in the rat cerebellum

Evidence based on the ability to accumulate [3H]noradrenaline by a mechanism sensitive to desmethylimipramine suggests that there is a period of hyperinnervation of the cerebellum by noradrenergic fibres around the beginning of the second postnatal week. Different developmental profiles for specific noradrenaline uptake and noradrenaline content indicate that invasion of the tissue by noradrenergic fibres precedes their full acquisition of transmitter. Developmental increases in the density of beta-receptors and adenyl cyclase responsiveness to isoproterenol lags behind those of the presynaptic components and does not begin until the hyperinnervation is declining around day 12.