颈部切口痛大鼠背根节神经元-卫星细胞交流对话规律与针刺镇痛的关系研究

Postoperative pain is a common form of acute pain in clinics,and acupuncture has been used for millennia to treat pain. Accumulating evidence indicates the efficacy of acupuncture for postoperative analgesia. But the mechanisms underlying the postoperative pain and the effect of acupuncture are still lacking. The neurons-glial cells-cytokines cross-talk in dorsal root gangliao(DRG) play an important role in hypersensitivity developing.But the contributions of DRG neurons-satellite cells cross-talk to acupuncture is poorly understood. We use a postoperative pain model induced by thyroid area incision, focusing on the neuron-satellite cells cross-talk, and investigate the activities of algogenic transmitters/transmodulators and proinflammatory cytokines on different time points after operation,which enhancing the pain transmitting, as well as the analgesic transmitter/transmodulators and anti-inflammatory cytokines, which weaken the nociceptive massage transmitting. Meanwhile, we compare the different effects of acupuncture on different acupoints to analyse the contribution of DRG to acupuncture on the postoperative pain in behavior,cell, mRNA and protein levels. This study concentrate on the relationship between the neuron-satellite cells cross-talk and the analgesic effect of aucpuncuture on postoperative pain. we hope that the result will be helpful to better define peripheral mechanisms underlying postoperative pain and acupuncture analgesia and also provide the evidence for acupoints selection under thyroid surgery with acupuncture anesthesia.

针刺可有效地缓解外科手术病人术后痛，但是其作用机制仍不清晰。外周初级感觉神经元的胞体所在的背根神经节（DRG）内感觉神经元-卫星胶质细胞-细胞因子交流对话是痛觉产生关键环节之一，但在针刺缓解术后痛中的作用机制尚无文献报道。本研究采用行为学、荧光免疫组化双标记、定量-PCR、免疫印迹等分子生物学技术，在颈部甲状腺区切口痛模型大鼠上，以DRG内神经元-卫星胶质细胞交互作用为切入点，观察颈部切口痛不同时程DRG内增强伤害性信息传递的兴奋性神经递质/调质、促炎细胞因子及减弱伤害性信息传递的抑制性递质/调质、抗炎细胞因子活动的规律，并比较电针扶突穴等不同穴区的作用的差异，探讨针刺对DRG内神经元、卫星细胞活动规律的影响与缓解术后痛的相关性，从整体、细胞、基因及蛋白表达水平上揭示针刺镇痛的DRG机制，为临床针刺麻醉开展甲状腺手术提供实验证据和理论基础。

针刺可以有效缓解外科手术病人术后痛，但是其作用机制仍不清晰。本研究在颈部切口痛大鼠模型上，从背根神经节（DRG）内感觉神经元-卫星胶质细胞-细胞因子交流对话为切入点，采用行为学、免疫组织学、RT-PCR、ELISA及WB等方法，观察到1）针刺扶突穴和合谷-内关穴可有效缓解颈部切口大鼠术后痛，镇痛效应优于足三里-阳陵泉穴；2）DRG内抑制性神经递质γ-氨基丁酸（GABA）的GABAAR（氯离子通道受体）在兴奋性SP肽能神经元有表达，针刺扶突穴与合谷-内关穴缓解颈部切口痛与DRG内GABA神经元的活性上调、GABAAR基因表达上调、SP、CGRP神经元活性下调有关；3）GABABR（G蛋白偶联受体）与NK-1R（SP受体）均在卫星细胞上有表达，IL-1RA（促炎细胞因子IL-1β的受体）在神经元上有表达，表明神经元与卫星胶质细胞间存在信息交流，针刺扶突与合谷-内关穴后卫星胶质细胞上GABABR的活性升高，同时卫星胶质细胞活性降低，促炎因子IL-1β,TNF-a,IL-6活性下调，卫星胶质细胞上的NK-1R活性减弱，神经元上的IL-1RA蛋白表达水平降低，同时抗炎因子IL-4基因表达水平上调；4）趋化因子Fractalkine和缝隙连接蛋白connexin43参与了术后痛痛敏的维持，针刺扶突与合谷-内关穴后，DRG内Fractalkine基因表达水平下调，connexin43免疫活性及蛋白表达下调。这些结果说明针刺扶突、合谷、内关穴的镇痛或麻醉效应可能部分通过调节DRG内神经元-卫星细胞-细胞因子之间的信息交流，增强抑制性神经元的活性，减弱兴奋性神经元与卫星胶质细胞间伤害性信息交流，最终减弱痛觉信息上传实现的，为临床针麻行甲状腺手术提供实验证据和选穴依据。