内脏伤害性传入易化穴位对大鼠脊髓广动力型神经元的激活效应  

Colorectal Nociceptive Signal Input Facilitates Impact of Acupoint Stimulation of “Zusanli”(ST 36)on Electrical Activities of Wide Dynamic Range Neurons in Lumbar Spinal Cord in Rats

作　　者：余玲玲[1,2] 李亮[2] 秦庆广[2] 贲卉[2] 荣培晶[2] 朱兵[2] 

机构地区：[1]武汉市中西医结合医院针灸科,武汉430022 [2]中国中医科学院针灸研究所,北京100700

出　　处：《针刺研究》2014年第5期390-395,共6页Acupuncture Research

基　　金：国家重点基础研究发展计划("973"计划)资助项目(No.2011CB 505200)

摘　　要：目的:探讨内脏处于生理和病理的不同状态,体表穴位功能的动态变化及其脊髓机制。方法:选用成年雄性SD大鼠22只,给予持续1min的80mmHg直结肠扩张(CRD)刺激作为内脏伤害性刺激,玻璃微电极细胞外记录L1-3节段脊髓背角广动力型(WDR)神经元活动,观察CRD刺激前后,不同强度电针(1mA、4mA、7mA、10mA)同侧"足三里"穴对WDR神经元激活率的效应。结果:CRD前,电针对WDR神经元放电活动的激活率分别为(18.12±13.56)%(1mA,P<0.05)、(152.38±36.19)%(4mA,P<0.001)、(231.21±49.74)%(7mA,P<0.001)、(331.54±61.89)%(10mA,P<0.01);而CRD刺激后,电针对WDR神经元的激活率分别为(226.78±39.59)%(1 mA,P<0.01)、(282.80±47.54)%(4 mA,P<0.001)、(343.06±58.35)%(7mA,P<0.01)、(338.62±80.04)%(10mA,P<0.01)。与CDR前的电针效应相比,CDR后,1mA、4mA、7mA的激活效应进一步增加(P<0.001,P<0.01),而10mA的激活效应无明显变化(P>0.05)。结论:内脏伤害性传入可以易化穴位对大鼠脊髓广动力型神经元的激活效应,表明体表穴位的功能和敏感程度在内脏病理状态下会增强,但是,这种穴位敏化效应在电针达到一定的刺激强度时又会达到一个平台期。Objective To observe changes of electrical activities of wide dynamic neurons（WDR）in the lumbar spinal cord after electroacupuncture（EA）stimulation of＂Zusanli＂（ST 36）during colorectal distension in rats,so as to analyze alternations of acupoint＇s functions under pathological conditions.Methods Experiments were performed in male Sprague-Dawley rats.Visceral nociceptive information input was generated by colorectal distension（CRD）.Extracellular discharges of WDR neurons in the dorsal horns of L1-3spinal cord were recorded using glass micropipettes and a microelectrode amplifier.EA stimulation（15Hz,1,4,7,10mA）was applied to ipsilateral＂Zusanli＂（ST 36）area.Results A total of 40 neurons were recorded in the present study.Under no CRD conditions,the firing rates of WDR neurons were significantly increased by（18.12±13.56）%（1mA）,（152.38±36.19）%（4mA）,（231.21±49.74）%（7mA）and（331.54±61.89）%（10mA）respectively after EA stimulation of ST 36.Under CRD conditions,the firing rates of these WDR neurons were increased by（226.78±39.59）%（1mA）,（282.80±47.54）%（4mA）,（343.06±58.35）%（7mA）,and（338.62±80.04）%（10mA）respectively after EA stimulation.It showed a considerablely increased sensitivity of electrical activities of WDR neurons to EA stimulation during CRD nociceptive stimulation.Conclusion Colorectal distension（visceral nociceptive stimulation）can strengthen the sensitivity of acupoint-EA stimulation-induced increase of firing rates of WDR neurons in the dorsal horns of the lumbar spinal cord in rats,suggesting apotentiation of the acupoint action under visceral nociceptive signal inputs.

关 键 词：穴位敏化 电针刺激 广动力型神经元 直结肠扩张 腰段脊髓 

分 类 号：R224.2[医药卫生—中医基础理论]