电针背俞穴对运动皮层下肢脑区皮质脊髓兴奋性的影响

Effects of Electro-Needling Back-Shu Points on Corticospinal Excitability of Lower Limb Motor Cortex

目的:观察电针背俞穴对运动皮层下肢脑区皮质脊髓兴奋性的作用,探讨经脉体表与体表(背腰部与下肢)的特定联系。方法:纳入20名健康受试者,采用交叉设计(每个受试者随机先后进入不同组别),观察电针心俞穴、肾俞穴对下肢胫骨前肌、腓肠肌和股内侧肌皮质脊髓兴奋性的影响。试验分为4组,A组(电针心俞穴组)、B组(电针肾俞穴组)、C组(假针心俞穴组)和D组(假针肾俞穴组)。运用单脉冲模式的经颅磁刺激,检测电针前后躯干部竖脊肌、TA、GA及VM的运动诱发电位、潜伏期和运动阈值。结果:电针后,A组和B组TA、GA、VM及ES的MEPs总波幅均较电针前显著增加(P<0.01),假针组(C组和D组)无明显变化。组间比较,A组与C组比较、B组与D组比较,TA、GA、VM及ES的MEPs总波幅差异均有统计学意义(P<0.01);A组与B组比较,电针后TA、GA及VM的MEPs总波幅差异无统计学意义(P>0.05)。电针前后,A组、B组、C组和D组TA、GA、VM及ES的MEPs潜伏期和运动阈值均无明显变化。结论:电针心俞穴、肾俞穴均可增强运动皮层下肢脑区TA、GA及VM的皮质脊髓兴奋性,提示背腰部与下肢之间可能存在特定联系。

Objective:To observe the effects of electro-needling back-Shu points on corticospinal excitability of lower limb motor cortex,and to explore the specific connections between the meridian system and the body surface(back,lumbar region and lower limbs).Methods:20 healthy subjects were included in the study,utilizing a crossover design(each subject randomly assigned to different groups in succession)to observe the effects of electro-needling Xinshu(BL15)and Shenshu(BL23)on the corticospinal excitability of the tibialis anterior(TA),gastrocnemius(GA)and vastus medialis(VM)muscles of the lower limbs.The subjects were divided into Group A(electro-needling BL15),Group B(electro-needling BL23),group C(sham electro-needling BL15)and group D(sham electro-needling BL23).Single-pulse transcranial magnetic stimulation was used to measure the motor-evoked potentials(MEPs),latency,and motor thresholds of the erector spinae(ES),TA,GA and VM muscles before and after electro-acupuncture(EA).Results:After the EA,the total amplitude of MEPs in TA,GA,VM and ES were significantly increased than that before the EA in group A and group B(P<0.01),there was no significant change in the sham EA groups(group C and group D).There were significant differences in the total amplitude of MEPs in TA,GA,VM and ES between group A and group C,also between group B and group D(P<0.01),but there was no significant difference in the total amplitude of MEPs in TA,GA and VM after the EA between group A and group B(P>0.05).There were no significant changes in the latency and motor threshold of MEPs in the four groups before and after the EA.Conclusion:EA can enhance the corticospinal excitability of TA,GA and VM in lower limb motor cortex,suggesting that there may be a specific connection between the back,lumbar region and lower limbs.