Effect of Etanercept on Mechanical Threshold of Pain in Rats with Chronic Sciatic Nerve Injury

NIU JiYuan; GUO Fuxiang; LIU Bing; SONG Qiang; MENG Qinglai; NIU Ke

Abstract：Objective To investigate the effect of etaneroept on mechanical hyperalgesia and expression of tumor necrosis factor-alpha in rat models with chronic constriction injury and to explore possible therapies to treat neuropathic pain. Methods The rat mod-els with neuropathic pain caused by sciatic nerve injury were established by ligating the sciatic nerves of one side. The rat models were randomly divided into two groups, the etaneroept group and the control group of normal saline, given 1 mg of etaneroept and normal saline respectively. The paw withdrawal mechanical thresholds before operation and 1, 3, 7, 14 days after operation were assessed and the expression changes of TNF-αin damaged sciatic nerves of the rats with CCI were observed. Results The expression of TNF-αin damaged sciatic nerves of the rats with CCI of the etaneroept group on Day 1, Day 3, Day7 after surgery was significantly lower than that of the control group, the paw withdrawal mechanical threshold on Day 7 and Day 14 of the former group remaining significantly higher than that in the latter one ( P< 0. 05 or 0. 01 ) . Conclusion The etanercept can lower the mechanical threshold of CCI rat models by decreasing the expression of TNF-α in damaged sciatic nerves.