【作者】 冯克辉；

【导师】 马骋；

【作者基本信息】 南京中医药大学 ， 针灸推拿学， 2010， 硕士

【摘要】 目的：近年来研究表明,神经病理性疼痛的产生与脊髓背角神经元中枢敏感化,以及脊髓背角神经元突触可塑性长时程增强的产生有密切的关系。研究长时程增强,以及针刺是否能抑制长时程增强的产生,对于研究神经病理性疼痛以及针刺治疗神经病理性疼痛的机制都有非常重要的意义。本实验采用坐骨神经分支选择性损伤(SNI)大鼠模型,观察电针对神经病理性疼痛大鼠痛阈和脊髓背角突触传递长时程增强的抑制作用,以进一步探讨神经病理性疼痛的发病机制以及针刺镇痛的机理。方法：健康成年雄性SD大鼠经筛选后,符合条件的大鼠随机分为假手术对照组和造模组。制备大鼠坐骨神经分支选择性损伤型神经病理性疼痛(SNI)模型。造模成功后随机将模型大鼠分为模型组和模型加电针干预组进行实验,模型组观察14日,于SNI术前、术后次日、第7天、第14天测定大鼠的机械痛阈；模型加电针干预组大鼠机械痛阈观察同模型组,但在第7天开始,用HANS穴位神经刺激仪2Hz,1mA电针环跳、委中穴30min,每日1次,连续7天。观察各组大鼠强直刺激后C纤维诱发场电位的变化,另外观察电针对模型组大鼠已形成并维持的LTP的抑制作用,即在模型组3h观察结束后,给予电针干预,参数时间同前,电针后观察1h。观察电针环跳、委中穴,对SNI模型大鼠机械痛阈和脊髓背角神经元突触传递LTP的干预作用。结果：1.SNI术后,大鼠双侧机械痛阈显著进行性降低,以术侧更为明显,与同时段假手术组比较有显著差异性(P<0.01)同时大鼠出现术侧后肢足趾卷曲、足外翻、以及步态异常等疼痛行为学的变化。2.电针干预后,大鼠术侧的机械痛阈值由电针前的20.6±2.6g提高至38.5±4.7g,明显高于同时段模型组(P<0.01),同时其疼痛行为异常也明显减轻。3.模型组大鼠C-纤维诱发场电位变化率在HFS诱导前、诱导后,以及诱导3h时分别为69.9±30.8%、224.9±98.5%和174.6±38.3%,,HFS诱导后C-纤维诱发场电位变化率显著高于基础平均值(P<0.01),而同时段假手术组HFS诱导后3h各个时段比较无统计学意义。4.模型加电针干预组大鼠电针后,C-纤维诱发场电位变化率在HFS诱导前、诱导后,以及诱导3h时分别为75.6±33.1%、73.3±20.3%和62.9±20.8%,与假手术组相当,与模型组比较有显著性差异(P<0.01)。5.对模型组已形成的脊髓背角神经元LTP,并稳定维持3 h的SNI模型大鼠施行电针干预,C-纤维诱发场电位变化率从电针前的182.8±29.7%降至34.0±16.3%,与电针前比较具有显著差异(P<0.01)。结论：神经病理性疼痛的产生与脊髓背角神经元突触可塑性长时程增强的形成以及脊髓背角神经元的中枢敏化有着密切的关系。电针可以显著抑制C纤维诱发电位LTP的形成,电针对LTP的维持具有有显著的阻断作用。同时电针可显著改善神经病理性疼痛模型大鼠的疼痛行为学变化。提示电针可能是通过抑制脊髓背角神经元突触可塑性变化的形成,减弱脊髓背角神经元的敏感化而发挥镇痛作用。更多还原

【Abstract】 Objective:In recent years, studies have shown that the generation of neuropathic pain is closely related to the and spinal cord dorsal horn neurons in sensitization,spinal cord dorsal horn neurons in long-term potentiation of synaptic plasticity.It has important significance to study acupuncture on treatment of neuropathic pain and neuropathic pain mechanism,long-term potentiation,and whether acupuncture can inhibit the production of long-term potentiation. This study is sciatic nerve injury in rat model of selective branches to observe the power for the pain threshold of neuropathic pain in rats and spinal cord dorsal horn synaptic transmission and long-term potentiation of the inhibitory effect in order to further explore the mechanism of acupuncture analgesia.Methods:Healthy adult male SD rats after screening, eligible rats were randomly divided into sham operation group, model group, and electro acupuncture intervention group. Selective Preparation of sciatic nerve branch injury neuropathic pain model (SNI) model. The model group observed 14 days and observed SNI before surgery, the next day, the 7th day, the first 14 days of determination of the mechanical pain threshold in rats; model of electro-acupuncture intervention mechanical pain threshold in rats to observe the same model group, but in the first 7 day one, with the HANS acupoint nerve stimulator 2Hz,1mA electro-acupuncture stimulate Weizhong and Huantiao for 30min, once a day for 7 days. Another observation is the inhibition effect of LTP electro acupuncture for the model group has been formed and maintained by, that is to say,observed the model group after the end of 3h given electro-acupuncture interventions, the parameter of time with the former, electro-acupuncture observed after 1h. Observation intervention effect of LTP of synaptic transmission use electro-acupuncture Huantiao and Weizhong to the SNI rats with mechanical pain threshold and spinal cord dorsal horn neurons.Results:1. After the operation of SNI, rats with bilateral mechanical pain threshold decreased significantly and more effect in operative side. At the same time, segment in sham group There were significant differences (P<0.01) while rats exhibited hind toe curling operative side, foot valgus, as well as pain and abnormal gait behavior changes.2. After use electro-acupuncture,the mechanical side surgery pain threshold by electro-acupuncture before 20.6±2.6g increased to 38.5±4.7g, significantly higher than the same time segment model group (P<0.01), while significantly reducing their pain and abnormal behavior.3. Model group C-fiber-evoked field potentials the rate of change in the HFS before induction, and after 3h induction, respectively for 69.9±30.8%,224.9±98.5% and 174.6±38.3%,, HFS induced C-fiber evoked field potential significantly higher than the rate of change of the basis of the average (P<0.01), while at the same segment in sham operation group at all time 3h after the induction of HFS was no statistical significance.4. Model of electro-acupuncture plus intervention in rats after electro-acupuncture, C-fiber-evoked field potentials the rate of change in the HFS before induction, and after 3h induction, respectively for 75.6±33.1%,73.3±20.3% and 62.9±20.8%, and the sham-operated group equivalent compared with the model group were significantly different (P<0.01).5. Group has been formed on the model of spinal cord dorsal horn neurons LTP, and to stabilize the maintenance of the SNI model rats 3 h the purposes of electro-acupuncture interventions, C-fiber-evoked field potentials from the electro-acupuncture before the rate of change of 182.8±29.7% down to 34.0±16.3%, with electro-acupuncture earlier significant differences (P<0.01).Conclusion:The production of neuropathic pain and spinal cord dorsal horn neurons in synaptic plasticity long-term potentiation, as well as the formation of the spinal cord dorsal horn neurons of the central sensitization has close relationship. Electro-acupuncture can significantly inhibit C fiber-evoked potentials of the formation of LTP, electricity for the maintenance of LTP has a significant role in blocking. At the same time, electro-acupuncture can significantly improve the rat model of neuropathic pain, pain behavior change. Electro-acupuncture may be prompted by inhibiting the spinal cord dorsal horn neurons in synaptic plasticity changes in the formation of reduced spinal cord dorsal horn neurons in sensitization exert analgesic effect.更多还原