ABSTRACT
Objective To clarify the actions of tranilast,an anti allergic drug,on chronic constriction mononeuropathy through an experiment using an animal model according to the method of Bennett et al. Methods 36 rats were divided into 2 groups: one was treated with tranilast(200mg/kg?d-1,p.o every experimental day),the other was controlled with solvent only. Chronological changes of heat evoked withdrawal latencies on a hot plate,nerve coducting velocitics, and histopathological changes were compared between the two groups from one to four weeks after loose ligation in the sciatic nerve. Results The changes of the withdrawal latency and nerve conducting velocities in the tranilast treatment group were significantly longer than those in the control. The rats without tranilast treatment showed inflammation in and around the constricted nerve bundles,axonal degeneration,phagocytes invasion and interstitial edematous changes at 7 days,numerous axonal sprouts and remyelination at 14 days,and regeneration in the nerve bundles at 28 days. In contrast,the rats treated with tranilast showed less inflammation or nerve fiber degeneration,and better regeneration than those of the control. Conclusion The actions of tranilast appear to have beneficial effects on prophylaxis of a chronic constriction mononeuropathy and on preservation of the nerve functions in rats.