苍白球电毁损对帕金森病大鼠HVSs 振荡波的影响研究

目的:应用直流电核团毁损术毁损帕金森病(PD)大鼠模型的内侧苍白球(GPi),记录其手术前后脑电生理活动的变化,以探讨内苍白球射频毁损术治疗PD的可能机制。方法:成年SD大鼠随机分为GP毁损组、假手术组及正常组。对PD毁损组和假手术组大鼠采用6-羟基多巴胺(6-OHDA)右侧黑质致密部(SNc)、中脑腹侧被盖区(VTA)两点注射法建立PD大鼠模型,并经腹腔注射阿扑吗啡(APO)诱发旋转以对模型建立进行评价。通过多导联宏电极在体脑电生理记录技术对各组大鼠进行右侧(注射侧)大脑皮层M1、M2区脑电及纹状体场电位的连续24小时记录,同时进行视频录像。对GP毁损组大鼠行直流电GPi毁损术,术后4天对各组大鼠均行阿扑吗啡诱导旋转行为检验,继续记录脑电活动,记录数据经频率谱分析及相干分析以揭示各记录位点信号的频率成分以及不同位点神经元集群间的功能连接和同步性。结果:对GP毁损组大鼠毁损术前后在清醒静息状态下的皮层脑电和纹状体场电位有明显改变,术后HVSs(High Voltage Spindles)在持续时间上明显缩短发作次数明显减少;对各组大鼠术后在静息状态下的脑电信号进行对比,GP毁损组大鼠较假手术组的HVSs持续时间和发作频率均减少并接近正常组大鼠水平,相干性分析显示GP毁损组大鼠术后在HVSs频段(5-13Hz)上的相干程度显著小于假手术组。结论:在清醒静息状态下6-OHDA建立的PD大鼠皮层-基底节环路上HVSs持续时间延长发生频率增高,经GP毁损术后其时间缩短发作次数减少同步性降低并接近正常水平,从而改善PD症状,该现象可能解释临床采用苍白球射频毁损术治疗PD的治疗机制。

Content the HVSs Changes Induced by Lesion of Pallidum in Rats with Parkinson's Disease

Objective: To explore the mechanism of radio frequency pallidotomy,use current lesion globus pallidus internus(GPi) of Parkinson rat,record the electrophysiology changes before and after the lesion.Methods: Adult SD rats were randomly divided into three groups: GP lesion group,sham surgery group and control.To build the model of PD in GP lesion and sham surgery group,these animals were received a injection of 6-hydroxydopamine(6-OHDA) into the right side substantia nigra pars compacta(SNc) and ventral tegmental area(VTA).Record the electrocorticogram(ECoG) in the primary(M1) and supplementary(M2) motor cortex and the local-field potential(LFP) in striatum for at least 24 hours.Then destroy the GP in the GP lesion group.Signals were analyzed using Frequency spectrum analysis and correlation analysis.Results: On rats of GP lesion group,in immobile waking state,the duration of High Voltage Spindles(HVSs) were shorter than that on rats of sham surgery group,and the number of HVSs were less;and close to the extent of control group.Conclusion:In immobile waking state,the HVSs episodes on PD rats was enhanced and the synchronization in cortex-basal ganglia(BG) was strengthen;but those were cut down to normal level after GP lesion.This phenomenon may explain the mechanism of pallidotomy which is use to treat PD patients.