OBJECTIVETo discuss the electrophysiologic effects of regenerative nerve fibres affected by control releasing of FK506.

METHODSFrom Mar. to Sep. in 2008, the body weigh of 32 Sprague-Dawley rats which was 200 to 250 g,anesthesia was performed with an intraperitoneal injection of 30 mg/kg 1% continal. The sciatic nerve was transected in each rat by the excision of a 10 mm gap just proximal to the trifurcation of the nerve. The 10 mm gap of sciatic nerve had been bridged with the new double channel nerve conduit of fusiform shape, which were randomly divided into two groups basing on the different drug in the channel, each group contained 16 animals. In group A,100 microl of chitin for medical use was injected into the conduit,in group B the two branches of the conduit respectively contained 100 microl of the chitin and 10 microl FK506 (group B2) or physiologic saline (group B1). At 8 and 12 week after operation, the morphology in regenerative nerve and electrophysiologic effects by detect compound muscle active potential (CMAP) and cortical somatosensory evoked potential (CSEP) were evaluated.

RESULTSThere were not significant differences of the regenerative nerve fibres between two channels in group A, but in group B2, the number of the regenerative fibres was much more than that in group B1. The latency of CMAP and CSEP in group B2 was shorter than that in group B1. But its amplitude was higher. There were highly significant difference between the groups (P < 0.01).

CONCLUSIONThe electrophysiologic effects of regenerative nerve fibres can be significantly promoted by FK506, which provide theory base for immunosuppressive treatment of peripheral nerve.