Selective survival of β1-adenergic receptors in rat cerebellum following neonatal X-irradiation

To investigate the cellular localization of β1- and β2-adrenergic receptors, the effects of intermittent neonatal X-irradiation focused on the cerebellum were determined on the densities of the two subtypes of β-adrenergic receptor. This treatment destroys the late-maturing cerebellar interneurons including the granule, basket and stellate cells. The total number of β2-adrenergic receptors per cerebellum was reduced by 81-83% in 6- and 12-week-old X-irradiated rats. However, the number of β1-adrenergic receptors per cerebellum in 6- and 12-week-old X-irradiated rats was not significantly different from that in control animals. The results suggest that β2 receptors in the rat cerebellum are primarily associated with the small interneurons destroyed by neonatal X-irradiation. The β1 receptors may be located on a cell population which is unaffected by this treatment, possibly on cerebellar Purkinje cells. (Auth.)