Ciani S
J Membr Biol. 1976 Dec 25;30(1):45-63. doi: 10.1007/BF01869659.
The steady-state electrical properties induced by neutral carriers of ions in lipid bilayer membranes and the time dependence of the membrane current for low applied voltages are described theoretically in terms of a model which allows for a voltage dependence of the interfacial reactions, as well as for a trapezoid shape of the internal free energy barrier for translocation of the complex. The basic features of the model are closely related to those of others presented previously (J.E. Hall, C.A. Mead & G. Szabo, 1973, J Membrane Biol. 11:75; S.B. Hladky, 1974, Biochim, Biophys. Acta 352:71, S.B. Hladky, 1975, Biochim, Biophys. Acta 375: 327; Eisenman, Krasne & Ciani, 1975, Ann. N.Y. Acad, Sci. 264:34), but the analysis of its consequences on the steady-state and nonsteady-state electrical characteristics is given here in greater detail and is extended to provide the expression for the zero-current potential in ionic gradients. It is shown that parameters, such as the width of the trapezoidal barrier, the plane of the reaction and the ratio constant of translocation across the membrane interior to the rate of constant of dissociation of the complex, can be deduced from steady-state analysis, whereas the individual values of these constants and the distance between the equilibrium positions of the complexes are deducible from relaxation measurements.
本文从理论上描述了脂质双分子层膜中离子中性载体诱导的稳态电学性质，以及低外加电压下膜电流的时间依赖性。所采用的模型考虑了界面反应的电压依赖性，以及复合物跨膜转运的内部自由能垒的梯形形状。该模型的基本特征与之前提出的其他模型密切相关（J.E. Hall、C.A. Mead和G. Szabo，1973年，《膜生物学杂志》11:75；S.B. Hladky，1974年，《生物化学与生物物理学学报》352:71；S.B. Hladky，1975年，《生物化学与生物物理学学报》375:327；Eisenman、Krasne和Ciani，1975年，《纽约科学院学报》264:34），但本文对其对稳态和非稳态电学特性影响的分析更加详细，并进行了扩展，以给出离子梯度中零电流电位的表达式。结果表明，诸如梯形势垒宽度、反应平面以及复合物跨膜内部转运速率常数与复合物解离速率常数之比等参数，可以从稳态分析中推导出来，而这些常数的具体值以及复合物平衡位置之间的距离则可以从弛豫测量中推导出来。
