电针对腰椎间盘突出症大鼠神经根形态及其NK1、NK2表达影响的实验研究

Experimental Study on Effects of Electroacupuncture on Morphology of Nerve Roots and Expressions of NK1 and NK2 in LDH Rats

目的为探索电针干预腰椎间盘突出症大鼠的作用机制,通过观察神经根形态及受体表达变化,阐明电针对神经损伤类疾病的治疗机理,验证经穴的循经特异性。方法健康SPF级SD大鼠雄性40只,按照随机数字表分为正常组、模型组、肾俞组、非经非穴组,每组10只。模型组麻醉后断尾,切开尾部椎间盘,取髓核制成混悬液。对L4-L5棘突间隙进行穿刺,使用9号腰椎穿刺针实行硬膜外穿刺,穿刺成功后,将自体髓核混悬液注射入大鼠体内。肾俞组造模方法同模型组,造模3 d后针刺大鼠肾俞穴,并连接电针仪,每天1次,治疗5次。非经非穴组造模方法同模型组,造模3 d后针刺大鼠非经非穴,治疗方法同肾俞组。取2 mm的L5神经根组织,苏木精-伊红(H-E)溶液染色,观察神经根形态改变;反转录梯度PCR方法检测P物质受体NK1、NK2mRNA的表达。结果肾俞组与模型组对比,出现再生髓鞘,整体排列规律,大小一致,炎性细胞浸润明显减少,细胞水肿不明显;而非经非穴组与模型组对照,依然有大量炎性细胞浸润,细胞界限不清楚,大小不一,排列不规则,细胞水肿明显,提示针刺肾俞穴能有效减轻神经根的炎性反应与水肿。模型组、肾俞组和非经非穴组的受体NK1R、NK2RmRNA表达水平与其对应空白组受体mRNA表达水平对比,差异有统计学意义(P<0.05);肾俞组的受体mRNA表达水平与对应模型组的对比,差异有统计学意义(P<0.05);非经非穴组的受体mRNA表达水平与对应肾俞组的对比,差异有统计学意义(P<0.05)。结论针刺肾俞穴治疗后,神经根形态较治疗前有明显的修复作用,受体NK1R、NK2RmRNA表达水平显著降低,说明针刺肾俞穴具有一定的修复神经镇痛抗炎作用。通过针刺疗效分析,肾俞组治疗效果明显优于非经非穴组,说明针刺肾俞穴对治疗腰椎间盘突出症有更好的治疗作用,进一步证明经穴的循经特异性。

Objective To explore the mechanism of electroacupuncture intervention in rats with lumbar disc herniation by morphological changes of nerve roots and changes in receptor expression and clarify the therapeutic mechanism of electroacupuncture on nerve injury diseases. Methods Forty healthy male SPF level SD rats, according to the digital table,were divided into normal group, model group, Shenshu(BL23) group and non-acupoint group, cases in each. In the normal group, no model was established, no acupuncture was given, and normal feeding was performed. After the model group was anesthetized, the tail was cut, the tail intervertebral disc was cut, and the nucleus pulposus was taken out to make a suspension.For L4-L5 spinous processes puncturing, the 9 th lumbar puncturing needle was used. After successful puncturing, the autologous nucleus pulposus suspension was injected into the body of rats. The model of Shenshu(BL23) group was the same as that of the model group. After 3 days of modeling, the rats were treated with electroacupunture at Shenshu(BL23) once a day for five times. The non-acupoint group’s modeling method was the same as that of the model group. After 3 days of modeling, the rats were needled. The method and course of treatment were the same as those of Shenshu(BL23) group. We took 2 mm of L5 nerve root tissue for hematoxylin-eosin(HE) solution to observe the changes of nerve root morphology. The expression of p-substance receptor NK1 and NK2 mRNA was detected by fluorescence quantitative(RT-PCR) method. Results Compared with the model group, the Shenshu(BL23) group appeared regenerative myelin sheath which was arranged regularly and had the same size. The inflammatory cell infiltration was significantly reduced and the cell edema was not obvious. The non-acupoint group had a large number of inflammatory cell infiltration. The cell boundaries were not clear, the size was different and the arrangement was irregular. There was obvious cell edema, suggesting that acupuncture at Shenshu(BL23) can effectively reduce nerves inflammatory reaction and edema. The expression levels of NK1 R and NK2 RmRNA in the model group, Shenshu(BL23) group and non-acupoint group were significantly different from those in the corresponding blank group(P<0.05). The expression level of receptor mRNA in Shenshup(BL23) group was significant compared with the that of the corresponding model group(P<0.05). There was a significant difference between the expression level of mRNA in the non-acupoint group and the corresponding Shenshu(BL23) group(P<0.05). Conclusion After eletroacupuncture at Shenshu(BL23), the morphology of nerve roots has obvious repairing effect before treatment. The expression levels of NK1 R and NK2 RM were significantly decreased, indicating that eletroacupuncture at Shenshu(BL23) has certain neurological analgesic and anti-inflammatory effects. Through the analysis of acupuncture efficacy, the treatment effect of Shenshu(BL23) group was significantly better than that of non-acupoint group, indicating that eletroacupuncture at Shenshu(BL23) has a better therapeutic effect on the treatment of lumbar disc herniation, and further proves the specificity of meridian points.