摘要
采用两态跳跃模型研究离子通道的通透机制,从两态动力学方程得到了平衡态下的能斯特方程、稳态条件下的米氏动力学关系。得出:若电压小于100mV,电导-电压关系是线性的;在电流-浓度关系中,电流具有饱和特性。这些与实验结果是一致的。此外,还讨论了钾离子通道到达稳态前的暂态过程,并用特征时间来描述这一过程。发现采用两态跳跃模型用较少的参数就可以说明离子通透的机制。
A two-state hopping model was proposed for studying the permeation of ion channel. The Nemst equation in equilibrium and the Michaelis-Menten relation in steady state were derived from the two-state kinetic model. The current-voltage relationship obtained in the symmetrical solutions case was linear when the applied potential was less than 100 mV that satisfied Ohm＇s law at higher applied potentials. The conductance-concentration relationship exhibited the saturation property. Moreover the characteristic time reached the steady state of the KcsA channel was also discussed.
出处
《生物物理学报》
CAS
CSCD
北大核心
2005年第4期289-294,共6页
Acta Biophysica Sinica
基金
国家自然科学基金项目(10375016
10474018)
河北省自然科学基金项目(A200400005)
关键词
钾离子通道
选择性过滤器
主方程
Potassium channel
Selectivity filter
Master equation
