葛根素对大鼠背根神经节神经病理性疼痛的镇痛作用

Analgesic Effect of Puerarin on Neuropathic Pain in the Dorsal Root Ganglion Neurons in Rats

目的探讨葛根素对大鼠背根神经节(DRG)神经病理性疼痛的镇痛作用。方法选取24只雄性SD大鼠,随机分为3组(n=8):手术组(SNL组,仅行脊神经结扎手术)、葛根素治疗组[Pue组,行脊神经结扎手术并鞘内注射葛根素(10μg/m L)]、假手术组(Sham组,不结扎脊神经,其他手术步骤同SNL组)。分别在术前和术后1、3、5、7 d检测各组大鼠的热缩足潜伏期(TWL)和机械缩足反应阈值(MWT),Western blotting和酶联免疫吸附法(ELISA)检测连续用药7 d后大鼠DRG炎性细胞因子的表达。结果与Sham组比较,SNL组、Pue组术后1、3、5、7 d MWT下降(均P<0.05);Pue组术后5、7 d MWT和TWL均高于SNL组(P<0.05)。与Sham组比较,SNL组DRG中炎性细胞因子IL-1β、IL-6表达均明显升高(P<0.05)。而Pue组DRG中IL-1β、IL-6表达较SNL组均明显下降(均P<0.05)。结论鞘内注射葛根素可缓解大鼠脊神经结扎所致的神经痛,下调DRG中炎性细胞因子IL-1β、IL-6表达,对神经病理性疼痛具有镇痛作用。

Objective To investigate the analgesic effect of puerarin(Pue)on neuropathic pain in rat dorsal root ganglions(DRG).Methods Twenty-four male SD rats were randomly divided into three groups:the SNL,Pue,and Sham group.The thermal withdrawal latencies(TWL)and mechanical withdrawal thresholds(MWT)of rats in each group were measured on preoperative day 0 and postoperative on 1,3,5,and 7 days,respectively.The changes in IL-1βand IL-6 in the DRG of rats in the 7-day postoperative group were detected by Western blotting and ELISA.Results At postoperative days 1,3,5,and 7 days,the MWT levels in the SNL,Pue group decreased(P<0.05)and reached the lowest level on postoperative day 7(P<0.05).The MWT and TWL in the Pue group was higher than the SNL group at postoperative days 5 and 7(P<0.05).The protein levels of IL-1βand IL-6 in DRG of the SNL group were significantly increased(P<0.05),whereas the levels were lower in Pue group than in the SNL group.Conclusion Intrathecal injection of Pue can relieve neuropathic pain caused by nerve ligation in rats,and could downregulate the expression of IL-1βand IL-6 in DRG,thus exerting an analgesic effect on neuropathic pain.