Fohlmeister J F, Adelman W J
Biophys J. 1985 Sep;48(3):391-400. doi: 10.1016/S0006-3495(85)83795-4.
A kinetic model of sodium activation gating is presented. The kinetics are based on harmonic analysis of gating current data obtained during large-amplitude sinusoidal voltage clamp in dynamic steady state. The technique classifies gating kinetic schemes into groups based on patterns of the harmonic content in the periodic gating current records. The kinetics that simulate the experimental data contain two independently constrained processes. The model predicts (a) sizable gating currents in response to hyperpolarizing voltage steps from rest; (b) a substantial increase in the initial peak of the gating current following voltage steps from prehyperpolarized potentials; (c) a small delay in the onset of sodium ion current following voltage steps from prehyperpolarized potentials; and (d) flickering during the open state in single channel current records. Although fundamentally different in kinetic structure from the Hodgkin-Huxley model, the present model reproduces the phenomenological development of Na conductance during the initiation and development of action potentials. The implications for possible gating mechanisms are discussed. A model gate is presented.
本文提出了一种钠激活门控的动力学模型。该动力学基于在动态稳态下进行大幅度正弦电压钳制时获得的门控电流数据的谐波分析。该技术根据周期性门控电流记录中的谐波含量模式将门控动力学方案分类。模拟实验数据的动力学包含两个独立约束的过程。该模型预测：(a) 从静息状态进行超极化电压阶跃时会产生相当大的门控电流；(b) 从预超极化电位进行电压阶跃后，门控电流的初始峰值会大幅增加；(c) 从预超极化电位进行电压阶跃后，钠离子电流开始出现小延迟；以及(d) 在单通道电流记录的开放状态期间出现闪烁。尽管本模型在动力学结构上与霍奇金-赫胥黎模型有根本不同，但它再现了动作电位起始和发展过程中钠电导的现象学发展。讨论了对可能的门控机制的影响。还提出了一个模型门。
