PERMEATION SELECTIVITY BY COMPETITION IN A DELAYED RECTIFIER POTASSIUM CHANNEL

被引：85

作者：

KORN, SJ ^{[1
]}

IKEDA, SR ^{[1
]}

机构：

[1] MED COLL GEORGIA, DEPT PHARMACOL & TOXICOL, AUGUSTA, GA 30912 USA

来源：

SCIENCE | 1995年 / 269卷 / 5222期

关键词：

D O I：

10.1126/science.7618108

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

Permeation selectivity was studied in two human potassium channels, Kv2.1 and Kv1.5, expressed in a mouse cell line. With normal concentrations of potassium and sodium, both channels were highly selective for potassium. On removal of potassium, Kv2.1 displayed a large sodium conductance that was inhibited by low concentrations of potassium. The channel showed a competition mechanism of selectivity similar to that of calcium channels. In contrast, Kv1.5 displayed a negligible sodium conductance on removal of potassium. The observation that structurally similar potassium channels show different abilities to conduct sodium provides a basis for understanding the structural determinants of potassium channel selectivity.

引用

页码：410 / 412

页数：3

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