标题： 一种关于活细胞膜电位的理论 显示英文标题

标题： A Theory for the Membrane Potential of Living Cells

摘要： 我们给出了细胞膜电位的显式公式，该公式以细胞内和细胞外离子浓度为依据，并推导了通过通道、交换器和电生泵流动的离子电流的方程。 我们证明泵所做的功等于细胞电势能的变化，加上通过通道和交换器的向下离子通量所损失的能量。 该理论在一个简单的心脏起搏细胞自发活动模型中得到了说明。 该模型预测了实验观察到的细胞内钾、钙和钠的离子浓度。 同样，模拟的动作电位形状和五种膜电流也与实验结果高度一致。 在长时间的模拟中，我们没有观察到浓度值的漂移，并且从细胞内和细胞外离子浓度相等的完全平衡状态开始时，我们得到了相同的渐近值。 显示英文摘要

摘要： We give an explicit formula for the membrane potential of cells in terms of the intracellular and extracellular ionic concentrations, and derive equations for the ionic currents that flow through channels, exchangers and electrogenic pumps. We demonstrate that the work done by the pumps equals the change in potential energy of the cell, plus the energy lost in downhill ionic fluxes through the channels and exchangers. The theory is illustrated in a simple model of spontaneously active cells in the cardiac pacemaker. The model predicts the experimentally observed intracellular ionic concentration of potassium, calcium, and sodium. Likewise the shapes of the simulated action potential and five membrane currents are in good agreement with experiments. We do not see any drift in the values of the concentrations in a long time simulation, and we obtain the same asymptotic values when starting from the full equilibrium situation with equal intracellular and extracellular ionic concentrations.