作　　者： ; ; ;

机构地区： 南方医科大学

出　　处： 《生物物理学报》 2011年第3期195-202,共8页

摘　　要： 采用膜片钳内面向外式记录技术,研究急性分离成年大鼠海马CAl区锥体神经元外向整流氯离子通道的氧化还原调控。发现细胞内侧给予氧化剂DTNB(5,5'-dithiobis-2-nitrobenzoic acid),可显著减弱氯通道的活动,IC50值为(28.05±2.42)μmol/L;还原剂DTT(dithiothreitol)对氯通道没有明显影响,但可逆转DTNB引起的抑制效应。说明DTNB不改变通道电导,其引起的通道活动减弱是由氯通道关闭时间延长而开放时间缩短所致。研究还发现,另一对氧化型和还原型谷胱甘肽具有与DTNB和DTT同样的效应。本研究结果显示,成年大鼠海马CA1区锥体神经元外向整流氯通道可以被细胞内氧化还原剂所调控。 Redox regulation of outwardly rectifying chloride channel（ORCC） was studied in acutely dissociated CA1 pyramidal neurons of adult rat hippocampus by using inside-out configuration of patch clamp techniques.Intracellular application of oxidizing agent 5,5＇-dithiobis-2-nitrobenzoic acid（DTNB） markedly decreased activity of chloride channels with an IC50 of（28.05±2.42） μmol/L.In contrast,the reducing agent dithiothreitol（DTT） had no apparent effect on channel activity but could reverse DTNB-induced enhancement.DTNB had no apparent effect on unitary conductance.The increase in channel activity produced by DTNB was due to prolonged open time as well as shortened close time.The effects exerted by another endogenous redox couple glutathione disulphide（GSSG,oxidized form） and its reduced form glutathione（GSH） were similar to DTNB and DTT.The present results indicate that outwardly rectifying chloride channel in CA1 pyramidal neurons can be modulated by intracellular redox agents.

关 键 词： 外向整流氯通道 氧化还原 海马 膜片钳 大鼠

领　　域： [生物学] [生物学]