藤壶肌纤维静息膜中阴离子和阳离子通透的机制。
Mechanisms of anion and cation permeations in the resting membrane of a barnacle muscle fiber.
作者信息
Hagiwara S, Toyama K, Hayashi H
出版信息
J Gen Physiol. 1971 Apr;57(4):408-34. doi: 10.1085/jgp.57.4.408.
The resting membrane of a barnacle muscle fiber is mostly permeable to cations in a solution of pH 7.7 whereas it becomes primarily permeable to anions if the pH is below 4.0. Mechanisms of ion permeation for various monovalent cations and anions were investigated at pH 7.7 and 3.9, respectively. Permeability ratios were obtained from the relationship between the membrane potential and the concentration of the test ions, and ionic conductances from current-voltage relations of the membrane. The permeability sequence for anions (SCN > I > NO(3) > Br > ClO(3) > Cl > BrO(3) > IO(3)) was different from the conductance sequence for anions (Br, Cl > ClO(3), NO(3) > SCN). In contrast, the permeability and conductance sequences were identical for cations (K > Rb > Cs > Na > Li). The results suggest that anion permeation is governed by membrane charges while cation permeation is via some electrically neutral mechanism.
藤壶肌纤维的静息膜在pH 7.7的溶液中对阳离子大多是可通透的，而如果pH低于4.0，它就主要对阴离子通透。分别在pH 7.7和3.9下研究了各种单价阳离子和阴离子的离子通透机制。渗透率是从膜电位与测试离子浓度之间的关系获得的，而离子电导则是从膜的电流-电压关系获得的。阴离子的通透顺序（SCN＞I＞NO₃＞Br＞ClO₃＞Cl＞BrO₃＞IO₃）与阴离子的电导顺序（Br、Cl＞ClO₃、NO₃＞SCN）不同。相比之下，阳离子的通透顺序和电导顺序是相同的（K＞Rb＞Cs＞Na＞Li）。结果表明，阴离子通透受膜电荷控制，而阳离子通透是通过某种电中性机制进行的。
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