Histochemical, ultrastructural and functional evidence for a neurogenic control of cerebrospinal fluid production from the choroid plexus.

Histochemical studies have shown that the rabbit choroid plexus receives a well-developed adrenergic and cholinergic nerve supply. The adrenergic innervation, which orginates almost entirely from the superior cervical sympathetic ganglia, begins to develop around birth and is fully established 3 weeks later. Electron microscopy has shown that the nerve terminals innervate both the plexus arterioles and its secretory epithelium. The sympathetic fibres have been shown to influence the plexus epithelium, as reflected by their effect on its carbonic anhydrase activity. They appear to have an inhibitory effect on the bulk CSF production, as revealed by electrical nerve stimulation and denervation experiments. The control seems to be excerted primarily on the plexus epithelium, though some of the effect may also be associated with alteration in choroid plexus blood flow.