胃溃疡小鼠背根节神经元兴奋性改变及穴位敏化状态的机制研究  

Research on mechanisms of acupoint sensitization in gastric ulcer mice from perspective of dorsal root ganglion neuronal excitability

作　　者：龙梦阳 胡瑞斌 刁志君 吴宇蔚 薛思梦 乔海法 LONG Meng-yang;HU Rui-bin;DIAO Zhijun;WU Yu-wei;XUE Si-meng;QIAO Hai-fa(College of Acupuncturemoxibustion and Tuina,Shaanxi University of Chinese Medicine,Xianyang 712046,Shaanxi Province,China;Traditional Chinese Medicine Master Research Institute,Shaanxi University of Chinese Medicine,Xianyang 712046,Shanxi Province;Xianyang Key Laboratory of Neurobiology(Acupuncture),Xianyang 712046,Shaanxi Province)

机构地区：[1]陕西中医药大学针灸推拿学院,陕西咸阳712046 [2]陕西中医药大学国医大师研究院,陕西咸阳712046 [3]陕西省咸阳市神经生物学(针灸)重点实验室,陕西咸阳712046

出　　处：《针刺研究》2023年第3期217-225,共9页Acupuncture Research

基　　金：国家自然科学基金项目(No.81873385、82074557);陕西中医药大学经脉-脏腑相关研究创新团队项目(No.YL-09)。

摘　　要：目的:从离子通道动力学角度探讨胃溃疡小鼠体表穴位敏化与背根节(DRG)中、小型神经元电生理活动的关系及机制。方法:雄性C57BL/6J小鼠随机分为对照组32只、模型组34只(死亡2只)。模型组于胃小弯近幽门处注射冰乙酸到胃壁肌层近黏膜下层复制胃溃疡模型,造模后6 d小鼠尾静脉注射伊文思蓝(EB)染色液,观察体表渗出点数量、部位及分布规律;HE染色观察小鼠胃组织病理形态变化;离体电生理结合生物素ABC法观察脊髓胸(T)9-T11节段DRG中、小型神经元全细胞膜电流和内在兴奋性水平。结果:对照组EB渗出点不明显,模型组体表EB渗出点密集分布于脊髓T9-T11节段支配区域及胃脘部、“中脘”“滑肉门”附近皮肤。与对照组比较,模型组胃组织黏膜下层有大量嗜酸性粒细胞浸润,胃小凹结构被破坏,胃底腺扩张。脊髓T9-T11节段内的DRG中型神经元Ⅰ型放电增加、Ⅱ型放电减少,跨膜电流密度升高(P<0.01),基强度降低(P<0.05),放电频率及放电数目增加(P<0.01,P<0.0001);DRG小型神经元Ⅰ、Ⅲ型放电减少,Ⅱ型放电增加,全细胞膜电流密度降低(P<0.01),放电频率及放电数目减少(P<0.01,P<0.0001)。结论:脊髓T9-T11节段内的DRG中、小型神经元通过不同的放电活动参与小鼠胃溃疡介导的穴位敏化过程。DRG神经元的内在兴奋性水平不仅能够动态编码穴位的敏化状态,而且可为内脏损伤导致穴位敏化的神经机制提供实验证据。Objective To investigate the relationship between acupoint sensitization on the body surface and neuronal intrinsic excitability of the medium-and small-size dorsal root ganglion(DRG)neurons from the perspective of ion channel kinetics in mice with gastric ulcer.Methods Male C57BL/6J mice were randomly divided into control(n=32)and model groups(n=34).The gastric ulcer model was established by injection of 60%glacial acetic acid(0.2 mL/100 g)into the gastric wall muscle layer and submucosa near the pylorus in the minor curvature of the stomach.In contrast,the same dose of normal saline was injected in the same way in the control group.Six days after modeling,Evans blue(EB)solution was injected into the mouse’s tail vein for observing the number and distribution of the exudation blue spots on the body surface.Histopathological changes of the gastric tissue were observed by H.E.staining.Then,whole-cell membrane currents and intrinsic excitability of medium-and small-size neurons in the spinal T9-T11 DRGs were measured by in vitro electrophysiology combining with biocytin-ABC method.Results In the control group,EB exudation blue spots were not obvious,while in the model group,the blue spots on the body surface were densely distributed in the area of spinal T9-T11 segments,the epigastric region,and the skin around“Zhongwan”(CV12)and“Huaroumen”(ST24)regions,and near the surgical incision region.Compared with the control group,the model group had a high level of eosinophilic infiltrates in the submucosa of gastric tissues,severe gastric fossa structure damage,gastric fundus gland dilation and other pathological manifestations.The number of exudation blue spots was proportional to the degree of inflammatory reaction in the stomach.In comparison with the control group,the spike discharges of type II of medium-size DRG neurons in T9-T11 segments were decreased,and the current of whole-cell membrane was increased,basic intensity was decreased(P<0.05),discharge frequency and discharge number were increased(P<0.01,P

关 键 词：穴位敏化 胃溃疡 背根节 神经元内在兴奋性 

分 类 号：R245.2[医药卫生—针灸推拿学]