Administration of the Influence of Shaoyao Gancao Decoction Extracts on IL-6 IL-1β and TNF-α in the Chronic Constriction Injury Rat Model of Neuropathic Pain

Objective:To observe the influence of the extracts of Shaoyao Gancao decoction(SGM)on mechanical allodynia and heat hyperalgesia induced by chronic constriction injury(CCI)of the sciatic nerve in rats and study the effect and the changes of IL-6,IL-1β and TNF-α.Methods:Mechanical allodynia and heat hyperalgesia were evaluated by mechanical withdrawal threshold(MWT)and thermalwithdrawal latency(TWL)respectively.Rats were divided randomly into five groups:NS group,sham group,CCI group,SGM group and control group.As the treatment groups,normal saline(2 μL)and SGM(120 mg/kg)were orally administered for 7 day after surgery.The TWL and MWT were measured before surgery and on days 1,3 and 7 after surgery.The levels of IL-6,IL-1β and TNF-α in spinal dorsal horn in rats were measured after surgery.Results:Compared to control and sham groups,rats with CCI had significantly decreased PWL and PWT from the first day after surgery to the end of this study(P0.01).SGM group had evidently increased the MWT and TWL(P0.01).Compared to control and sham groups,rats with CCI had significantly increased IL-6,IL-1β and TNF-α(P0.01),SGM group had evidently decreased IL-6,IL-1β and TNF-α in comparison to NS group(P0.01).Conclusion:SGM oral administeration can evidently increase the MWT and TWL of CCI rats.The decreases of IL-6,IL-1β and TNF-α may be related to the analgesia of SGM.