电针不同频率对坐骨神经损伤大鼠脊髓Bcl-2、Bax及p53表达的影响

Effect of Different Frequency Electroacupuncture on Expressions of Bcl-2、Bax and p53 of Spinal Cord in Rats with Sciatic Nerve Injury

目的观察不同的电针频率对坐骨神经损伤大鼠脊髓Bcl-2、Bax及p53表达的影响;探究周围神经损伤后抑制神经元凋亡的最佳电针频率。方法将48只SD大鼠(雌雄各半)随机分为低频组、高频组、模型组、空白组。制作坐骨神经钳夹损伤模型,造模成功第8天低频组和高频组均针刺"环跳"穴并分别给予2 Hz、100 Hz不同频率的电针干预,20 min/次·d^-1,连续14 d。检测大鼠坐骨神经功能指数(SFI)、HE染色观察坐骨神经形态学改变、Western Blot及免疫组织化学法测定Bcl-2、Bax及p53的表达。结果坐骨神经功能指数检测,低频组、高频组SFI较模型组升高(P<0.01),且低频组优于高频组(P<0.01)。HE染色,模型组神经纤维排列紊乱,雪旺细胞增多,髓鞘及轴突发生裂解消失,低频组、高频组神经纤维在数量及排列紊乱程度等方面均有改善,且低频组优于高频组。Western Blot和免疫组织化学检测,模型组、低频组、高频组中Bcl-2、Bax及p53的表达与空白组比较均有统计学意义;与模型组相比,低频组和高频组中Bcl-2显著升高,Bax、p53显著下降;并且低频组Bcl-2表达高于高频组(P<0.05),低频组Bax及p53的表达低于高频组(P<0.05)。结论电针有抑制或延缓神经细胞凋亡的作用;大鼠周围神经损伤后,2 Hz的治疗频率在抑制神经细胞凋亡的作用中优于100 Hz。

Objective To observe the effect of electroacupuncture frequency on the expressions of Bcl-2,Bax and p53 in rats with sciatic nerve injuryand explore the best treatment frequency on the treatment of peripheral nerve injury.Method Forty-eight SD rats(bisexual each 24)were randomly divided into low frequency group,high frequency group,model group and blank group.The sciatic nerve clamp injury model was set up.The electroacupuncture intervention was started on the 8 th day after model establishment.The low frequency group and the high frequency group were used to acupuncture at"Huantiao"(GB30)and the electroacupuncture at different frequencies of 2 Hz and 100 Hz was given respectively for 15 min each time and lasted for 14 consecutive days.The sciatic nerve function index(SFI)was recorded and calculated.Pathological changes of the sciatic nerve were displayed by HE staining.The expressions of Bal-2,Bax and p53 were detected by Western blotting and immunohistochemistry.Results The sciatic nerve function index(SFI)values were increased in the low frequency group and the high frequency group compared with that of the model group(P<0.01)and the low frequency group was superior to the high frequency group(P<0.01).HE staining showed the nerve fibers of the model group arranged at random and schwann cells increased,the axon and myelin almost completely disappeared.The nerve fibers of low frequency group and high frequency group wereimprovedin quantity and disorder degree,and were better those of the low frequency group.Western blotting and immunohistochemistry showed the expressions of Bcl-2,Bax and p53 in low frequency group,high frequency group and model groupwere statistically significant compared with those of the blank group.Compared with the model group,Bcl-2 was significantly increased and Bax and p53 were significantly decreased in the low frequency group and the high frequency group.The Bcl-2 expression in the low frequency group was higher than that ofthe high frequency group(P<0.05).The expressionsof Bax and p53 in the high frequency group were lower than those of the high frequency group(P<0.05).Conclusion Electroacupuncture can inhibit the apoptosis of nerve cells.After the peripheral nerve injury,the inhibition of neuronal apoptosis in the frequency of 2 Hz is better than that in the frequency of 100 Hz.