干扰海马spastin表达通过抑制突触传递介导小鼠认知功能障碍  

Interfering spastin expression in hippocampus mediates cognitive dysfunction of mice by inhibiting synaptic transmission

作　　者：李志坤 祝玮 王晗婕 郑雪峰 郭国庆[1] 张吉凤[1] LI Zhi-kun;ZHU Wei;WANG Han-jie;ZHENG Xue-feng;GUO Guo-qing;ZHANG Ji-feng(Department of Anatomy,Neuroscience Laboratory for Cognitive and Developmental Disorders,School of Medicine,Jinan University,Guangzhou,510632,China)

机构地区：[1]暨南大学基础医学与公共卫生学院解剖学系,认知与发育障碍神经科学创新实验室,广东广州510632

出　　处：《中国病理生理杂志》2021年第5期779-788,共10页Chinese Journal of Pathophysiology

基　　金：国家自然科学基金资助项目(No.81771144,No.81571191);广东省自然科学基金重点项目(No.2017B030311002);广东省自然科学基金面上项目(No.2021A1515011134)。

摘　　要：目的:探讨微管切割蛋白spastin对小鼠认知功能的影响。方法:构建干扰spastin的重组腺相关病毒载体,通过立体定位注射至C57BL/6小鼠海马CA1区。利用新事物认知实验和Morris水迷宫实验分析小鼠的认知功能;利用高尔基染色法分析海马CA1区锥体细胞的形态;采用脑片膜片钳技术分析CA1区神经元的突触传递功能。结果:新事物认知实验显示干扰海马spastin的表达后,小鼠对新事物的探索时间及次数均减少(P<0.05);水迷宫实验显示干扰组小鼠在目标象限的持续时间及穿越目标象限的次数均减少(P<0.05);高尔基染色实验显示,干扰spastin的表达可使基树突和顶树突的树突棘密度显著降低且成熟树突棘显著减少(P<0.05);膜片钳检测可见,干扰spastin的表达后,小鼠海马CA1区锥体细胞的微小兴奋性突触后电流(mEPSC)的振幅和频率以及诱发的EPSC最大幅度均显著降低且长时程增强(LTP)受损(P<0.05)。结论:干扰海马CA1区spastin的表达可抑制突触传递而介导小鼠认知功能障碍。AIM:To explore the effect of microtubule-severing protein spastin on the cognitive function in mice.METHODS:A recombinant adeno-associated virus(rAAV)vector that interfering the expression of spastin was constructed,and then was stereotactically injected into the hippocampal CA1 area of C57 BL/6 mice.Novel object recogni-tion and Morris water maze experiments were performed to analyze the cognitive function of mice.Golgi staining was per-formed to analyze the morphological changes of hippocampal pyramidal cells.Brain slice electrophysiological recording was performed to analyze the synaptic transmission in hippocampal CA1 neurons.RESULTS:Novel object recognition ex-periment showed that the time and bouts of sniffing novel object were reduced in spastin interference group(P<0.05).The Morris water maze demonstrated that the duration in the target quadrant and the times of crossing over the target quad-rant were also reduced in spastin interference mice(P<0.05).Golgi staining showed that the density of basal dendritic spines and apical dendritic spines was decreased significantly in spastin interference mice,mainly due to the reduction of mature dendritic spines(P<0.05).Moreover,the amplitude and frequency of miniature excitatory postsynaptic currents(mEPSC)in CA1 pyramidal cells of spastin interference mice were significantly reduced(P<0.05).Similarly,the maxi-mum amplitude of evoked EPSC in CA1 pyramidal cell of spastin interference mice also reduced and long-term potentiation(LTP)was impaired(P<0.05).CONCLUSION:Interfering the expression of spastin in hippocampal CA1 region medi-ates cognitive dysfunction of mice by inhibiting synaptic transmission.

关 键 词：微管切割蛋白 认知功能障碍 树突棘 突触传递 

分 类 号：R749.16[医药卫生—神经病学与精神病学] R363.2[医药卫生—临床医学]