γ-氨基丁酸能抑制对大棕蝠听皮层神经元声反应特性的影响  

EFFECT OF GABAergic INHIBITION ON PROPERTIES OF AC NEURONS IN RESPONSE TO SOUND STIMULATION

作　　者：陈其才[1] JenP 吴飞健 

机构地区：[1]华中师范大学生物科学系,湖北武汉430079 [2]Division of Biological Sciences

出　　处：《生物物理学报》2001年第1期79-85,共7页Acta Biophysica Sinica

基　　金：国家自然科学基金!;国家教育部基金!(#39740002和 #96 -146)资助项目

摘　　要：为了探讨γ -氨基丁酸 (γ -aminobutyricacid ,GABA)能抑制对大棕蝠 (Eptesicusfuscus)听皮层 (auditorycortex ,AC)神经元声反应特性的影响 ,采用多管微电极电泳方法 ,观察了8只大棕蝠AC神经元去GABA能抑制前后声刺激诱发的反应。结果显示 ,微电泳GABAa受体拮抗剂荷包牡丹碱 (bicuculline ,Bic)去GABA能抑制可改变声刺激诱发的反应模式 ;极大地增加神经元冲动发放率 ,缩短反应的潜伏期和降低反应的最小阈值 ;不同程度地改变强度 -发放率和强度-潜伏期函数。结果提示 :1、GABA能抑制对AC神经元声信号处理起重要作用 ;2、GABA能抑制可改变AC神经元兴奋性支配或输入的效应 ,并因此定型AC神经元的声反应性质 ,即发放模式、阈值、强度 -发放率和强度 -潜伏期函数 ;3、GABA能抑制为AC神经元的声诱发活动提供一种调制性抑制。In order to determine the effect of GABAergic inhibition on the discharge patterns and properties of AC neurons in response to sound stimulation, we studied the responses of 8 big brown bats (Eptesics fuscus) induced by sound stimulation before and after GABAergic inhibition eliminated by bicuculline application. In the present study, we observed that GABAergic inhibition can change both the discharge pattern of response elicited by sound stimulation, intensity-rate and -latency functions, increase the firing rates of cortical neurons greatly, shorten the latencies, and decrease the minimum threshold. These results demonstrated: 1. GABAergic inhibition plays an important role in sound signal processing of AC neurons. 2. GABAergic inhibition could modify effect of the excitatory innervation or input projecting to AC neurons, and determine the response properties of AC neurons, such as discharge patterns, minimum threshold, rate- and latency-intensity functions; 3. GABNAergic inhibition could present a modulated-inhibition for AC neurons's activity evoked by sound stimulation.

关 键 词：GABA能抑制 声反应特性 AC神经元 听皮层 大棕蝠 Γ-氨基丁酸 

分 类 号：Q437[生物学—生理学]