Objective: To observe the effect of acupuncture at "Houxi"(SI3) and "Huantiao"(GB30) on high mobility group box 1(HMGB1) protein and mRNA in spinal nerve trunk(SNT) of rats with lumbar disc herniation(LDH), so as to explore the mechanisms of acupuncture at this paired points on the treatment for LDH.
Methods: SD rats were randomly divided into sham operation, model, conventional acupuncture(CA) and paired points(PP) groups (with 8 rats in each group). The LDH model was established by injection of autologous suspension made from rats' own nucleus pulsus into the epidural space. Rats in the CA group received acupuncture treatment at bilateral "Weizhong"(BL40), "Dachangshu"(BL25) and "Shenshu"(BL23), while rats in the PP group received acupuncture at bilateral SI3 and GB30, 30 min each time, once daily for 14 consecutive days. The thermal pain threshold of bilateral hind feet of rats was detected by thermal pain stimulator. The contents of serum IL-1β, IL-6 and IL-8 of rats were detected by ELISA. Western blot and immunofluorescence were used to detect the expression of HMGB1 protein in the lumbar(L)5 SNT of rats. The relative expression of HMGB1 mRNA in L5 SNT was determined by qPCR. HE staining was used to observe the morphological changes of L5 SNT.
Results: Compared with the sham operation group, the thermal pain threshold of bilateral hind feet in the model group was decreased (P<0.05); compared with the model group, the thermal pain threshold of bilateral hind feet in the CA group and the PP group were increased (P<0.05). The expressions of HMGB1 protein and mRNA in L5 SNT, and the contents of serum IL-1β, IL-6 and IL-8 of rats in the model group were significantly increased(P<0.000 1, P<0.001) in contrast to the sham operation group. The expressions of HMGB1 protein and mRNA in L5 SNT, and the levels of serum IL-1β, IL-6 and IL-8 were significantly decreased (P<0.01, P<0.000 1, P<0.001, P<0.05) in the CA and PP group, in comparison with those of the model group. Compared with the CA group, the above indexes of rats in the PP group recovered more significantly (P<0.05,P<0.001, P<0.01,P<0.000 1). The histomorphological results showed scattered and various-sized nerve fibers, vacuolation, a large number of disintegrating myelin sheath and lysed Schwann cells in the model group. Myelin sheaths regeneration, regularly-arranged nerve fibers were seen in the CA group and the PP group, with more obvious histopathological recovery observed in the PP group than the CA group.
Conclusion: Acupuncture intervention inhibites the expressions of HMGB1 protein and mRNA in rats with LDH, and further reduces the production of IL-1β, IL-6 and IL-8, which is beneficial to inflammatory response inhibition and pain alleviation. The therapeutic effect of the PP group is more obvious than that of the CA group.
目的：观察针刺“后溪”“环跳”对腰椎间盘突出症(LDH)大鼠脊神经干高迁移率族蛋白1(HMGB1)蛋白和mRNA表达的影响，探讨针刺对穴“后溪”“环跳”治疗LDH的作用机制。方法：SD大鼠随机分为假手术组、模型组、普针组、对穴组，每组8只。采用非压迫自体髓核混悬液注射法制备腰椎间盘髓核突出大鼠模型。普针组针刺双侧“委中”“大肠俞”“肾俞”，对穴组针刺双侧“后溪”“环跳”，两组均每次30 min，每日1次，连续治疗14 d。采用热痛刺激仪检测大鼠双后足热痛阈；ELISA法检测大鼠血清白细胞介素(IL)-1β、IL-6、IL-8含量；Western blot法及免疫荧光染色法检测大鼠腰(L)5脊神经干HMGB1蛋白表达水平；荧光定量PCR法检测大鼠L5脊神经干HMGB1 mRNA相对表达量；HE染色法观察L5脊神经干组织形态变化。结果：与假手术组比较，模型组双后足热痛阈降低(P<0.05),与模型组比较，普针组、对穴组双后足热痛阈升高(P<0.05)。与假手术组比较，模型组脊神经干HMGB1蛋白、mRNA表达及血清IL-1β、IL-6、IL-8含量明显升高(P<0.000 1，P<0.001)；与模型组比较，普针组和对穴组脊神经干HMGB1蛋白、mRNA表达及血清IL-1β、IL-6、IL-8含量明显降低(P<0.01，P<0.0001，P<0.001，P<0.05)，对穴组较普针组降低更明显(P<0.001，P<0.01，P<0.000 1，P<0.05)。模型组神经纤维排列散乱，大小不一，大量髓鞘崩解、空泡样改变，施万细胞大量溶解；普针组及对穴组出现再生髓鞘，神经纤维排列较为规律，对穴组较普针组恢复更为明显。结论：针刺干预抑制了LDH大鼠HMGB1蛋白和 mRNA的表达，从而进一步减少IL-1β、IL-6、IL-8的产生，抑制炎性反应，改善疼痛，对穴组的治疗效果较普针组更为明显。.
Keywords: Acupuncture; High mobility group box 1; Houxi(SI3); Huantiao(GB30); Lumbar disc herniation; Paired points.