The localization of the β-subtype of protein kinase C (PKC-β) in rat sympathetic neurons

Abstract

The localization of PKC-β was studied in rat sympathetic neurons using a polyclonal antibody specific for the β1- and β2-subspecies. The tissues studied included the superior cervical (SCG) and hypogastric (HGG) ganglia and the target tissues of the SCG and HGG neurons: the submandibular gland, iris, prostate and vas deferens. PKC-β-LI was found in nerve fibers in both ganglia. A proportion of the fibers in the SCG disappeared after decentralization, suggesting that the fibers were of both pre- and postganglionic origin. The somata of the HGG and SCG neurons expressed varying amounts of PKC-β-LI, the majority of SCG neurons being labelled only after colchicine treatment. In all target tissues there were PKC-β-immunoreactive nerve fibers in bundles, but the most peripheral branches of the fibers were negatively labelled. The results show that PKC-β-LI is widely present in sympathetic postganglionic neurons with mainly quantitative differences. The lack of PKC-β in the most peripheral branches of nerve fibers might be a general feature of sympathetic postganglionic neurons, suggesting that the participation of PKC-β in neurotransmitter release and in other functions in nerve terminals in sympathetic adrenergic neurons is unlikely.