摘要
目的:观察电针对神经病理性疼痛大鼠痛阈和背根神经节(DRG)、脊髓微透析液及脊髓组织匀浆中兴奋性氨基酸(EAAs)神经递质含量的影响。方法:SD大鼠随机分成对照、模型、假模型、电针、假电针5组,每组10只。制备坐骨神经分支损伤(SNI)模型:双结扎并切断一侧坐骨神经的分支腓总神经和胫前神经,仅留腓肠神经。于造模前1天,造模次日,第4、7、9、15日,测定大鼠自由状态下损伤侧机械和热痛阈。第9日开始,电针(2Hz,起始1mA,每10min增加1mA,共30min)和假电针组(插针不通电)分别电针和假电针"环跳"和"委中"穴进行干预,1次/d,共7d。第15日收集样品,用OPA柱前衍生高效液相色谱法测定EAAs神经递质含量。结果:电针可显著扭转SNI模型大鼠的机械痛阈下降(P<0.01);假电针也有显著效果(P<0.05),但与电针仍有差异(P<0.05)。模型组脊髓微透析液中EAAs显著增加(P<0.01);经电针或假电针干预后,透析液中谷氨酸(Glu)显著减少(P<0.01),电针引起的变化大于假电针(P<0.01)。脊髓组织匀浆中Glu含量模型组显著增多(P<0.01);电针可显著降低之(P<0.01),假电针也有类似作用(P<0.05)。脊髓组织匀浆中天门冬氨酸(Asp)含量的变化及电针、假电针干预后的结果与Glu类似。结论:电针对神经病理性疼痛SNI模型有显著镇痛作用,该作用与电针显著抑制脊髓背角兴奋性氨基酸神经递质的释放密切相关。
Objective To observe the effect of electroacupuncture （EA） on pain threshold and contents of excitatory amino acids （EAA） in dorsal root ganglia （DRG） and spinal cord in rats with neuropathic pain. Methods Fifty SD rats were randomly divided into control （C） ,model （M）, sham-model （SM）, EA, and sham-EA groups, with 10 cases in each. Neuropathic pain （spared nerve injury, SNI） model was established by cutting off the right common peroneal nerve and proso-tibial nerve （with the sural nerve reserved intact）. Before and after surgery, the mechanical pain threshold （MPT） and thermal pain threshold （TPT） were measured respectively on the injured side under consciousness state. EA （2 Hz, 1 - 3 mA, adding 1 mA/10 rain） was applied to ＂Huantiao＂ （GB 30） and ＂Weizhong＂ （BL 40） on the affected side for 30 rain. For rats of sham-EA group, filiform needles were inserted into GB30 and BL40 simply without manipulation or electrical stimulation. The treatment was given once daily for 7 days. On the 15^th day, the rats were sacrificed for sampling right L4 -L6 DRG and spinal cord. The contents of neurotransmitters, glutamate （Glu） and aspartic acid （Asp） in DRG and spinal cord were detected with high performance liquid chromatography （HPLC）. Micro-dialysis technique was used to collect the dialysate from the spinal cord, homogenated for measuring EAA by HPLC. Results In comparison with control group, after SNI, MPT decreased significantly from the 1^st day on in model group. Compared with model group, on the 15th day, MPT increased significantly in both EA and sham-EA groups （P〈0.05, 0.01）,but MPT of sham-EA was significantly lower than that of EA group （P〈0.05）. No significant changes were found in TPT in 5 groups （P〉0.05）. It suggested that sham EA still had an analgesic effect in spite of being lower than that of true EA. Compared with control group, the contents of Glu and Asp in the spinal cord tissue and micro-dialysate in model group increased significantly after SNI （P〈0.01）. In comparison with model group, the contents of Glu in DRG and spinal cord tissue and micro-dialysate, and Asp in the spinal cord tissue and micro-dialysate in both sham-EA and EA groups decreased considerably （P〈0. 05, 0.01）. D（alysate Glu and spinal cord tissue Asp contents in EA were remarkably lower than those in sham-EA group （P〈0.01, 0.05）. Conclusion EA has a significant analgesic effect in SNI rats, which is closely related with its effect in inhibiting the release of Glu and Asp from dorsal horns of the spinal cord and lowering contents of EAAs.
出处
《针刺研究》
CAS
CSCD
2008年第4期250-254,共5页
Acupuncture Research
基金
江苏省自然科学基金资助项目(BK2006239)
江苏省高校自然科学重大基础研究项目基金(05KJA36011)
