锌离子对急性分离的大鼠骶髓后连合核神经元GABA_A受体介导电流的抑制作用(英文)  

Zn^(2+) DEPRESSES GABA_A RECEPTOR MEDIATED RESPONSES IN ACUTELY DISSOCIATED SACRAL DORSAL COMMISSURAL NEURONS

作　　者：庞志平[1] 王殿仕[1] 徐天乐[1] 李继硕[1] 

机构地区：[1]第四军医大学解剖学教研室,梁銶琚脑研究中心,西安710032

出　　处：《生理学报》1998年第6期649-655,共7页Acta Physiologica Sinica

基　　金：国家自然科学基金!39770248

摘　　要：采用制霉菌素穿孔膜片箝技术，研究了锌离子（Zn2+）对急性分离的大鼠骶髓后连合核神经元GABAA受体介导电流的作用。结果表明：（1）在箝制电压为-40mV时，GABA可通过GABAA受体介导产生内向电流；（2）此电流可被Zn2+呈非电压依赖性可逆地阻断；（3）在Zn2+存在的情况下，GABA的浓度-效应曲线平行右移。上述结果提示，Zn2+可能通过变构调控机制对GANAA介导的反应产生抑制作用。The effects of Zn2+ on GABAA-receptor mediated responses in acutely isolated rat sacral dorsal commissural nucleus (SDCN) were studied using nystatin-perforated whole cell rechniques .The results demonstrated that (1) GABA induced inward currents through activation of GABAA^at a holding potential of-40 mV; (2) GABAA-receptor mediated responses were suppressed by Zn2+ in a reversible and voltage-independent manner; and (3) in the presence of Zn2+, the concentration-response curve of CABA-induced responses was shifted to the right in a parallel manner. The results suggest that Zn2+allosterically depresses GABAA-receptor mediated currents.

关 键 词：ZN^2+ GABAA受体 骶髓后连合核 电流 神经元 

分 类 号：Q424[生物学—神经生物学]