你不要把voltage-sensor 和 离子通道等同起来。 你这个结论直觉上不对。离子电流的产生大致有四个阶段:voltage-sensor激活-> voltage-sensor 形变->离子通道形变->自由离子(free ion)通过。其中两个形变过程 通常会被假设为瞬间发生,所以剩下两个过程,“voltage-sensor激活”和“自由离子 通过“共同决定了Pi/Po. 比如在这篇review文章里面,就专门提到"The substitution of hydrophobic residues in S4 segment of Smith-Maxwell et al. (90) and Ledwell and Aldrich (48) indicates a high degree of cooperativity in the last step of channel opening, which was incorporated as one more concerted step in the three-state four-subunit model and built in for the eight-state model." 如果我理解没错的话,voltage-sensor 未激活/激活的概率应该不等同于离子通道打开的概率Po,更确切说voltage-sensor激 活的概率是离子通道概率的一部分;尤其影响离子通道模型的最后一步。 【1】The Voltage Sensor in Voltage-Dependent Ion Channels,FRANCISCO BEZANILLA,PHYSIOLOGICAL REVIEWS, 2000. 说,