全细胞膜片钳研究离体小鼠下丘亚核神经元电生理特性  

In vitro whole-cell patch clamp recordings of neurons in subnuclei of mouse inferior colliculus

作　　者：刘玲[1] 杜小凤[1] 付欣[1] 李慧[1] 贾慧娟[1] 王欣[1] 罗峰[1] 陈其才[1] 

机构地区：[1]华中师范大学生命科学学院遗传调控与整合生物学重点实验室,武汉430079

出　　处：《生理学报》2015年第4期370-378,共9页Acta Physiologica Sinica

基　　金：supported by the National Natural Science Foundation of China(No.31300915);a starting grant from Scientific Foundation of Central China Normal University;China(No.120002040402)

摘　　要：下丘(inferior colliculus,IC)是听觉通路的重要中继站。本实验采用红外可视脑片全细胞膜片钳技术对昆明小鼠IC神经元的电生理特性进行研究。共记录获得88个神经元,其中背侧核(dorsal cortex of IC,ICd)神经元21个,中央核(central nucleus of IC,ICc)神经元43个,外侧核(external cortex of IC,ICx)神经元24个。根据神经元对注入正电流的发放模式,将其分为起始型(6.8%,n=6),适应型(39.8%,n=35)和持续型(53.4%,n=47)三种类型。约一半的神经元(49/88)具有超极化电流激活的内向电流(hyperpolarization-activated inward current,Ih)。ICd和ICc神经元主要表现为持续型(61.9%和67.4%),ICx主要为适应型(75%)。比较发现,ICd、ICc及ICx神经元之间在动作电位发放阈值和膜时间常数等参数上存在显著差异。以上结果表明IC亚核神经元的电生理特性存在差异,这些差异可能与神经元的类型、它们所接受的投射以及在声信息处理中作用不同相关。The inferior colliculus （IC） is a pivot along the central auditory pathway. Using infrared visual whole-cell patch clamp recording technique, we investigated the electrophysiological properties of IC subnuclei neurons. Recordings were made from 88 neurons, including 21 neurons from the dorsal cortex of the IC （ICd）, 43 neurons from the central nucleus of the IC （ICc） and 24 neurons from the external cortex of the IC （ICx）. Based on the responses to positive current injection, three firing patterns, i.e., onset （6.8%, n = 6）, adapting （39.8%, n = 35） and sustained （53.4%, n = 47） patterns, were identified. The hyperpolarization-activated inward current （Ih） could be recorded in half of the neurons （49/88）. The sustained pattern occurred in more than half of ICd and ICc neurons （61.9% and 67.4%）, while the adapting pattern occurred in majority of ICx neurons （75%）. Action potential （AP） threshold and time constant also showed significant differences across neurons from the ICd, the ICc and the ICx. Our results indicate that IC neurons are different in electrophysiological properties across the subnuclei. The variance of the responses may be related to the distinct types of neurons as well as the received projections, which is implicated in the distinct roles of IC neurons in central auditory processing.

关 键 词：全细胞膜片钳 下丘 发放类型 小鼠 

分 类 号：Q42[生物学—神经生物学]