小鼠初级听皮层SOM中间神经元突触输入的时空特性研究  

Spatial-temporal characteristics of synaptic inputs received by SOM^+ interneurons in mouse primary auditory cortex

作　　者：王丽娟[1] 陶璨[1] 张光伟[1] 周畅[1] 闫素梅[1] 熊鹰[1] 周艺[1] 

机构地区：[1]第三军医大学基础医学部神经生物学教研室、重庆市神经生物学重点实验室、重庆市神经科学研究所,重庆400038

出　　处：《第三军医大学学报》2017年第5期417-422,共6页Journal of Third Military Medical University

基　　金：国家自然科学基金面上项目(31371116,31271177,31471056)~~

摘　　要：目的研究小鼠初级听皮层SOM+神经元接受刺激后突触输入的时空特性。方法通过局部场电位记录方法对初级听皮层进行定位后,采用电压钳全细胞记录方法在离体脑片上分别记录SOM+神经元和锥体神经元在接受刺激后诱发的兴奋后突触后电流和抑制性突触后电流。通过对两类神经元的兴奋性突触后电流和抑制性突触后电流时间特性以及幅度上的比较,从而分析SOM+神经元突触输入的时空特性。结果 SOM+神经元与锥体神经元的突触输入在时间特性上表现出相似的起始潜伏期。SOM+神经元的兴奋性突触后电流和抑制性突触后电流的峰值潜伏期[(14.35±2.74)ms,(18.26±3.24)ms]明显要短于锥体神经元的兴奋性突触后电流和抑制性突触后电流的峰值潜伏期[(18.81±3.76)ms,(21.08±3.93)ms],差异具有统计学意义(EPSC P<0.05,IPSC P<0.01)。在突触后电流的幅度上两类神经元差异没有统计学意义(P>0.05)。结论 SOM+中间神经元接受的突触输入与锥体神经元接受的突触输入在基本电生理特性上类似,但时间特性上的差异提示两者接受的突触输入在皮层内环路来源上可能存在一定差异。Objective To investigate the spatial-temporal characteristics of synaptic inputs received by somatostatin positive （SOM＆＋ ） interneurons in mouse primary auditory cortex （A1）. Methods After localization of primary A1 with local field potential （LFP） recording, the synaptic inputs, including excitatory and inhibitory postsynaptic currents （EPSCs and IPSCs ） were recorded in the SOM^＋ interneuron and pyramidal cells using voltage-clamp whole-cell recording. The time course and amplitude of EPSCs and [PSCs were compared between the SOM^＋ interneurons and pyramidal cells to analyze the spatial-temporal characteristics of the inputs received by SOM＋＋ interneurons. Results The SOM^＋ interneurons and pyramidal cells showed similar temporal profile, with no significant difference found in the onset latency of both EPSC and IPSC. The peak latency of EPSC was 14.35 ± 2.74 ms and that of IPSC was 18.26 ± 3.24 ms in the SOM^＋ interneurons, which were significantly shorter than those of pyramidal cells （EPSC, 18.81 ± 3.76 ms, P 〈0.05; IPSC： 21.08 ± 3.93 ms, P 〈 0.01 ）. However, there were no significant differences in the amplitude of either EPSC or IPSC between the SOM^＋ interneurons and pyramidal cells （ P 〉 0. 05 ）. Conclusion The synaptic inputs received by SOM interneurons are similar in basic electrophysiological properties to those by pyramidal cells. Yet the temporal differences indicate that the sources of synaptic inputs received by these 2 types of neurons might be different.

关 键 词：SOM+神经元 锥体细胞 全细胞记录 离体膜片钳 初级听皮层 

分 类 号：R-332[医药卫生] R338.2