Effects of nerve decompression on cytokines expression of diabetic peripheral neuropathy rats

Objective To explore effects of nerve decompression on cytokines expression on dorsal root ganglion of diabetic peripheral neuropathy(DPN)rat models. Methods Diabetic mellitus models were induced by streptozocin(STZ)in 50SD rats.Two weeks later,32successfully induced diabetic rats were randomly assigned into diabetic mellitus group(DM,n=8),diabetic peripheral neuropathy group(DPN,n=12),and diabetic peripheral neuropathy decompression group(DPND,n=12).Rats in DM group didn't receive any treatment.Rats in DPN and DPND groups were given sciatic compression operation.Six weeks later,rats in DPNP were given thorough nerve decompression operation,and rats in DPN were given pseudo nerve decompression operation.Mechanical threshold was measured using Von Frey filaments at different times before and after compression and decompression operation respectively(before,2weeks and 6weeks after operation).Six weeks later,pathological changes were observed,and cytokines expression,such as TNF-α,COX-2,VEGF,and GAP-43in dorsal root ganglion of rats of all the three groups were detected by ELISA method. Results Mechanical threshold of DPND rats was improved after 6weeks decompression operation than before operation in DPN group(P0.05).Six weeks after decompression operation,phenomenon of inflammatory reaction and swelling were less in DPND group than in DPN group,TNF-αand COX-2expression were less in DPND group than in DPN group,and decrease of TNF-αhad statistical significance.VEGF and GAP-43expression were increased in DPND group than in DPN group,but there were no statistical significance. Conclusion Peripheral nerve decompression can significantly improve high mechanical pain threshold induced by nerve compression,and this may have some relation with its regulative effect on expression of some cytokines in dorsal root ganglion.