Pacinian corpuscles in rats with carbon disulphide neuropathy.

Adult Wistar rats were exposed to carbon disulphide vapours at a concentration of 2.4 mg/l of air for 5 days a week (6 h a day), and the ultrastructure of Pacinian corpuscles and their nerve supply was investigated after 6 months of exposure. Both degenerative and regenerative changes were observed in sensory axons and the corpuscles. In a sample of corpuscles examined, 30% were denervated and about 60% showed clear signs of reinnervation. Some of the reinnervated corpuscles were supplied by unmyelinated axons. In others, one to three myelinated axons were already found at the nerve entry. The axons branched and formed three to eight terminals in the inner core. Due to continuous intoxication, most regenerated terminals were again undergoing degeneration. In peripheral nerves, the evidence of axonal regeneration has been reported in various toxic distal axonopathies. However, the reinnervation of Pacinian corpuscles has not been described before. It can be expected that reinnervation of Pacinian corpuscles and other end-organs also occurs in other axonopathies, if not during continuous poisoning, then at least after its cessation.