丘脑背内侧核损毁对帕金森病大鼠内侧前额叶皮层电活动的影响  

Effect of mediodorsal thalamic nucleus lesions on electrical activity in medial prefrontal cortex of rats with Parkinson’s disease

作　　者：范玲玲[1,2] 丁书平 沈国民[1,2] 胡志红[1] 任爱红[1] 邓博 FAN Lingling;DING Shuping;SHEN Guomin;HU Zhihong;REN Aihong;DENG Bo(Department of Physiology,School of Basic Medical Sciences,Henan University of Science and Technology,Luoyang 471000,China;School of Basic Medical Sciences,Henan University of Science and Technology,Henan International Joint Laboratory of Thrombosis and Hemostasis,Luoyang 471000,China;Department of Basic Courses,Luoyang Polytechnic,Luoyang 471023,China)

机构地区：[1]河南科技大学基础医学院生理教研室,河南洛阳471000 [2]河南科技大学基础医学院河南省血栓与止血国际联合实验室,河南洛阳471000 [3]洛阳职业技术学院公共基础教学部,河南洛阳471023

出　　处：《吉林大学学报（医学版）》2022年第6期1382-1388,共7页Journal of Jilin University：Medicine Edition

基　　金：国家自然科学基金项目(81770140);河南省科技厅科技攻关项目(222102310362)。

摘　　要：目的:探讨丘脑背内侧核(MD)损毁对帕金森病(PD)模型大鼠内侧前额叶皮层(m PFC)锥体神经元电活动的影响,阐明MD在PD病理生理过程中的作用。方法:以6-羟基多巴胺(6-OHDA)脑内注射损毁黑质致密部(SNc)复制PD大鼠模型,在大鼠脑中注射鹅膏蕈氨酸(IBO)损毁MD。将24只雄性SD大鼠随机分为正常组、SNc损毁组(PD模型组)、MD损毁组(MD中注射IBO)和SNc+MD联合损毁组(SNc损毁后1周损毁同侧MD),每组6只。酪氨酸羟化酶免疫组织化学染色观察各组大鼠SNc和腹侧被盖区(VTA)中多巴胺神经元数量,尼氏染色判断电生理记录点的位置和MD损毁情况。观察各组大鼠m PFC中锥体神经元的放电频率、放电间隔(ISI)的变异系数和放电形式。结果:注射6-OHDA后,PD模型组大鼠损毁侧SNc中多巴胺神经元完全消失,同侧VTA中多巴胺神经元数较对侧明显减少(P<0.01);与正常组比较,SNc损毁组大鼠m PFC锥体神经元的放电频率明显升高(P<0.05),放电形式趋于爆发式活动(P=0.001),平均ISI变异系数增加(P<0.01);MD损毁2周后,SNc损毁组大鼠m PFC锥体神经元的放电频率较正常组明显增加(P<0.01),爆发式放电增多(P<0.01),平均ISI的变异系数增加(P<0.01);与正常组比较,SNc+MD联合损毁组大鼠m PFC锥体神经元的放电频率差异无统计学意义(P>0.05),爆发式放电增多(P<0.01),平均ISI的变异系数增加(P<0.01)。结论:MD对m PFC神经元的活动起重要的调节作用,MD的功能改变可能是PD病理生理过程中m PFC神经活动改变的重要原因之一。Objective:To investigate the effect of mediodorsal thalamic nucleus(MD) lesions on the electrical activity of the pyramidal neurons in the medial prefrontal cortex(mPFC) of the rats with Parkinson’s disease(PD),and to clarify the role of MD in the pathophysiological process of PD.Methods:The rat model of PD was established by injecting 6-hydroxydopamine(6-OHDA) into the substantia nigra pars compacta(SNc)of the rats,and MD was damaged by intracerebral injection of ibotenic acid(IBO). A total of 24 male SD rats were divided into normal group,SNc lesion group(PD model group),MD lesion group(injected with IBO in MD),and SNc+MD combined lesion group(ipsilateral MD lesion 1 week after SNc lesion),and there were 6 rats in each group. The numbers of dopaminepositive neurons in SNc and ventral tegmental area(VTA)of the rats in various groups were detected by tyrosine hydroxylase immunohistochemical staining,and Nissl staining was used to determine the location of the electrophysiological recording points and extent of the MD lesion. The firing frequencies and coefficients of variation of average interspike interval(ISI),and discharge patterns of pyramidal neurons in mPFC of the rats in various groups were observed. Results:After injection with 6-OHDA,the dopamine neurons in the damaged SNc of the rats in PD model was completely disappeared,and the number of dopaminergic neurons in ipsilateral VTA in the contralateral side was significantly decreased(P<0. 01);compared with normal group,the firing frequency of mPFC pyramidal neurons of the rats in SNc lesion group was significantly increased(P<0. 05),the firing pattern tended to bursting activity(P=0. 001),and the coefficient of variation of average ISI was increased(P<0. 01);two weeks after MD lesion,the firing frequency of mPFC pyramidal neurons of the rats in SNc lesion group was significantly higher than that in normal group(P<0. 01),the bursting firing was increased(P<0. 01),and the coefficient of variation of average ISI was increased(P<0. 01);compared with normal

关 键 词：帕金森病 内侧前额叶皮层 锥体神经元 丘脑背内侧核 电生理 

分 类 号：R742.5[医药卫生—神经病学与精神病学]