Effects of methylcobalamin, gliclazide and their combination on peripheral nerve function and polyol pathway in streptozotocin diabetic rats

OBJECTIVE: To investigate the effects of methylcobalamin, gliclazide and their combination on peripheral nerve function and polyol pathway in streptozotocin diabetic rats. METHODS: The diabetic rats induced by streptozotocin intraperitoneal injection were administerted orally for 8 weeks. Effects of drugs on sciatic nerve morphological alterations, motor nerve conduction velocity, Na⁺, K⁺-ATPase activity and aldose reductase activity, sciatic nerve polyol contents were determined respectively. RESULTS: Compared with diabetic group, the sciatic nerve morphological alterations was improved, sciatic nerve conduction velocity increased, aldose reductase activity depressed and Na⁺, K⁺-ATPase activity increased in each group, respectively. The sorbitol and fructose contents were decreased in combination group. The glucose contents were reduced in gliclazide and combination groups. CONCLUSION: Methylcobalamin, gliclazide and their combination improve metabolism and function of peripheral nerve in streptozotocin diabetic rats. Synergistic action on polyol pathway was observed in drug combination group.