Pang Z P, Wang D S, Xu T L, Li J S
Department of Anatomy and K.K. Leung Brain Research Centre, Fourth Military Medical University, Xi'an 710032.
Sheng Li Xue Bao. 1998 Dec;50(6):649-55.
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 recording techniques. The results demonstrated that (1) GABA induced inward currents through activation of GABAA-receptor 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 GABA-induced responses was shifted to the right in a parallel manner. The results suggest that Zn2+ allosterically depresses GABAA-receptor mediated currents.
采用制霉菌素穿孔全细胞记录技术，研究了锌离子（Zn2+）对急性分离的大鼠骶髓后连合核（SDCN）中γ-氨基丁酸A型受体（GABAA受体）介导反应的影响。结果表明：（1）在-40 mV的钳制电位下，γ-氨基丁酸（GABA）通过激活GABAA受体诱导内向电流；（2）Zn2+以可逆且电压非依赖性的方式抑制GABAA受体介导的反应；（3）在存在Zn2+的情况下，GABA诱导反应的浓度-反应曲线平行右移。这些结果提示，Zn2+通过变构作用抑制GABAA受体介导的电流。
