TIME COURSE OF TEA+-INDUCED ANOMALOUS RECTIFICATION IN SQUID GIANT AXONS
TIME COURSE OF TEA+-INDUCED ANOMALOUS RECTIFICATION IN SQUID GIANT AXONS
复制标题
DOI：
10.1085/jgp.50.2.491
复制
发表时间：
1966-01-01
影响因子：
3.8
通讯作者：
ARMSTRONG, CM
中科院分区：
文献类型：
--
作者：
ARMSTRONG, CM
在电压钳电流的变化鱿鱼巨大的轴突所造成的低轴质TEA+（四乙基氯化铵）浓度（0.3米[图片]和以上）进行了描述。它们分别是：（a）对于海水中静息电位的正阶跃，K+电流增加、减少，然后增加，而不是单调增加。(b)对于440 m[image]外部K+中静息电位的正阶跃，电流具有指数衰减分量，其衰减率随轴浆[TEA+]增加。控制电流单调增加。(c)对于440 m[image]外部K+中静息电位的负阶跃，电流记录有一个峰值，随后是相对于对照缓慢的衰减。控制记录单调递减。定性地说，这些发现可以通过一个简单的动力学模型来描述，从该模型中，通过一个假设，可以计算K+离子通过K+通道的速率。从（c）得出的一个有趣的结论是，通道不能被正常的电压敏感机制（由Hodgkln和Huxley描述）关闭，直到不含TEA+。
Changes in the voltage clamp currents of a squid giant axons wrought by low axoplasmic TEA+ (tetraethylammonium chloride) concentrations (0.3 m[image] and above) are described. They are: (a) For positive steps from the resting potential in sea water, the K+ current increases, decreases, then increases, instead of increasing monotonically. (b) For positive steps from the resting potential in 440 m[image] external K+, the current has an exponentially decaying component, whose decay rate increses with axoplasmic [TEA+]. The control currents increase monotonically. (c) For negative steps from the resting potential in 440 m[image] external K+, the current record has a peak followed by a decay that is slow relative to the control. The control record decreases monotonically. Qualitatively these findings can be described by a simple kinetic model, from which, with one assumption, it is possible to calculate the rate at which K+ ions move through the K+ channels. An interesting conclusion from (c) is that the channels cannot be closed by the normal voltage-sensitive mechanism (described by Hodgkln and Huxley) until are free of TEA+.