壮医经筋推拿对神经病理性疼痛大鼠的镇痛机制研究

A study on the analgesic mechanism of Zhuang Medicine meridian massage in neuropathic pain rats

目的探讨壮医经筋推拿对神经病理性疼痛(NPP)大鼠的镇痛机制。方法将45只SD大鼠随机分为模型组、正常组、壮医经筋推拿组、假推拿组、假手术组,每组9只。除正常组和假手术组,其余三组均建立L_(5)脊神经结扎(SNL)模型。于术后第1天开始对假推拿组(轻抚摸其双后肢)和壮医经筋推拿组进行干预,连续干预14 d,其余三组不予推拿或抚摸干预。于术前,以及术后1 d、3 d、14 d对各组大鼠测定机械缩足反射阈值(PWMT)和热刺激回缩潜伏期(PWTL)。于术后第14天通过实时荧光定量聚合酶链式反应(RT-qPCR)法检测大鼠L_(4-6)脊髓背角caspase-1的表达水平,采用酶联免疫吸附试验(ELISA)法检测血清白细胞介素(IL)-18表达水平,采用微板法检测血清乳酸脱氢酶(LDH)的表达水平。结果术前五组大鼠PWMT和PWTL比较差异无统计学意义(P>0.05)。术后1 d、3 d,与正常组比较,其余四组的PWMT和PWTL均显著降低(P<0.05)。术后14 d,壮医经筋推拿组的PWMT和PWTL高于模型组和假推拿组,差异有统计学意义(P<0.05)。术后14 d,模型组脊髓背角组织caspase-1以及血清IL-18、LDH表达水平较正常组显著增高(P<0.05)。与模型组、假推拿组相比,壮医经筋推拿组脊髓组织的caspase-1以及血清中IL-18、LDH的表达水平更低,差异有统计学意义(P<0.05)。结论壮医经筋推拿可减轻SNL模型大鼠痛敏反应,其机制与下调脊髓背角caspase-1表达,以及抑制细胞焦亡介导的免疫炎症反应有关。

Objective To explore the analgesic mechanism of Zhuang Medicine meridian massage in neuropathic pain(NPP)rats.Methods Forty-five Sprague-Dawley(SD)rats were randomly divided into model group,normal group,Zhuang Medicine meridian massage group,sham massage group,and sham operation group,with 9 rats in each group.An L 5 spinal nerve ligation(SNL)model was established in the other three groups except the normal group and the sham operation group.Interventions were started on the first day after operation in the sham massage group(gently touching the rats′hind limbs)and the Zhuang Medicine meridian massage group for 14 consecutive days,while the other three groups did not receive massage or touching intervention.The paw withdrawal mechanical thresholds(PWMT)and the paw withdrawal thermal latency(PWTL)were measured in the rats in each group before operation and 1,3 and 14 days after operation.On the 14th day after operation,the expression of caspase-1 in the dorsal horn of the L 4-6 spinal cord in the rats was detected by real-time quantitative polymerase chain reaction(RT-qPCR),and the expression of interleukin-18(IL-18)in the serum was detected by enzyme-linked immunosorbent assay(ELISA),and the expression of lactate dehydrogenase(LDH)in the serum was detected by microplate method.Results There were no significant differences in PWMT and PWTL among the five groups before operation(P>0.05).Compared with those in the normal group,the PWMT and PWTL in the other four groups were significantly decreased on the 1st day and the 3rd day after operation(P<0.05).On the 14th day after operation,the PWMT and PWTL in the Zhuang Medicine meridian massage group were higher than those in the model group and the sham massage group,and the differences were significant(P<0.05).On the 14th day after operation,the expression levels of caspase-1 in the spinal dorsal horn tissues and the serum IL-18 and LDH in the model group were significantly higher than those in the normal group(P<0.05).Compared with those in the model group and the sham massage group,the expression levels of caspase-1 in the spinal cord tissues and the serum IL-18 and LDH in the Zhuang Medicine meridian massage group were lower,and the differences were significant(P<0.05).Conclusion Zhuang Medicine meridian massage can alleviate pain sensitivity in the SNL model rats,and its mechanism is related to down-regulating the expression of caspase-1 in the dorsal horn of the spinal cord and inhibiting the immune inflammatory reaction mediated by pyroptosis.