Bezanilla F, Armstrong C M
Philos Trans R Soc Lond B Biol Sci. 1975 Jun 10;270(908):449-58. doi: 10.1098/rstb.1975.0022.
Associated with the opening and closing of the sodium channels of nerve membrane is a small component of capacitative current, the gating current. After termination of a depolarizing step the gating current and sodium current decay with similar time courses. Both currents decay more rapidly at relatively negative membrane voltages than at positive ones. The gating current that flows during a depolarizing step is diminished by a pre-pulse that inactivates the sodium permeability. A pre-pulse has no effect after inactivation has been destroyed by internal perfusion with the proteolytic enzyme pronase. Gating charge (considered as positive charge) moves outward during a positive voltage step, with voltage dependent kinetics. The time constant of the outward gating current is a maximum at about minus 10 mV, and has a smaller value at voltages either more positive or negative than this value.
与神经膜钠通道的开放和关闭相关的是电容性电流的一个小成分，即门控电流。去极化步骤终止后，门控电流和钠电流以相似的时间进程衰减。在相对负的膜电压下，两种电流的衰减都比在正电压下更快。去极化步骤期间流动的门控电流会被一个使钠通透性失活的预脉冲所减弱。在用蛋白水解酶链霉蛋白酶进行内部灌注破坏失活后，预脉冲没有作用。在正电压阶跃期间，门控电荷（被视为正电荷）以电压依赖性动力学向外移动。向外门控电流的时间常数在约 -10 mV 时最大，在比该值更正或更负的电压下具有较小的值。
