[目的]探讨低频电针干预早期神经痛对背根神经节(dorsal root ganglion,DRG)辣椒素受体(Transient receptor potential vanilloid type 1,TRPV1)磷酸化与痛敏相关神经肽降钙素基因相关肽(calcitonin gene-related peptide,CGRP)与P物质(substance P,SP)的抑制作用。[方法]SD大鼠随机分为正常组、假手术组、模型组与电针组,每组8只。模型组采用脊神经结扎(spinal nerve ligation,SNL)的方法制作大鼠神经痛模型。电针组采用2 Hz电针治疗,选取患侧"足三里"、"昆仑"穴,连续3d。检测D1、D3大鼠术侧后足缩腿阈(Paw withdrawal threshold,PWT),D3 L5 DRG p-TRPV1、CGRP、SP水平。[结果]SNL模型大鼠早期即出现自发性疼痛,PWT显著下降(P〈0.001),L5 DRG p-TRPV1水平升高(P〈0.001),CGRP水平升高(P〈0.05),SP水平下降(P〈0.05)。SNL假手术组大鼠PWT没有显著变化。2 Hz电针能提高SNL模型大鼠的PWT(P〈0.001),降低L5 DRG p-TRPV1水平(P〈0.05)与CGRP水平(P〈0.01),对SP水平没有显著影响。[结论]早期神经痛与DRG p-TRPV1、CGRP水平升高有关。低频电针能下调DRG p-TRPV1与CGRP水平,改善早期神经痛。
[Objective] To investigate the inhibitive effects of electroacupuncture(EA) with low frequency on DRG p-TRPV1,CGRP and SP during early neuropathic pain.[Methods] SD rats were randomly divided into Normal,Sham spinal nerve ligation(SNL),SNL,and SNL +EA groups,8 animals per group.Rat neuropathic pain model was made by right L5 SNL in SNL group.2 Hz EA was administered at ipsilateral points Zusanli and Kunlun for consecutive 3 days in SNL +EA group.D1 and D3 PWT,D3 L5 DRG TRPV1 phosphorylation(p-TRPV1),CGRP and SP levels were measured.[Results] Rats in Sham SNL group had no obvious change in PWT,while rats in SNL group developed spontaneous pain and had a significant reduction in PWT(P〈0.001).L5 DRG p-TRPV1 and CGRP levels were increased(P〈0.001,P〈0.05),while SP level was reduced(P〈0.05) in SNL rats.2 Hz electroacupuncture up-regulated SNL rats PWTs(P〈0.001),reduced L5 DRG p-TRPV1 and CGRP levels(P〈0.05,P〈0.01),and had no significant effect on L5 DRG SP level.[Conclusion] Early neuropathic pain was associated with up-regulation of DRG p-TRPV1 and CGRP.Electroacupuncture with low frequency could alleviate early neuropathic pain through reducing DRG p-TRPV1 and CGRP levels.