FINKELSTEIN A
Biophys J. 1964 Nov;4(6):421-40. doi: 10.1016/s0006-3495(64)86793-x.
The central purpose of this paper is to elucidate in a well defined system the meaning of certain phenomena and concepts associated with the active transport of ions. To this end a specific model for a carrier system which actively transports a single ionic species is analyzed and discussed in detail. It is assumed in this model that the carrier-mediated ionic transport occurs in regions of the membrane physically separate from those regions in which free ionic movement takes place,-coupling between the active and passive regions of the membrane occurring through local current flows. The model is seen to display the following characteristics: (a) Starting from identical solutions on the two sides of the membrane, there is produced a redistribution of ions; (b) with identical solutions on the two sides of the membrane there exists a potential difference across the membrane, i.e., the "pump" is electrogenic; (c) the "short circuit" current for symmetrical solutions is equal to the flux of the neutral ion carrier complex; (d) the rate of active transport (and hence of metabolism) is dependent on the ionic concentrations in the surrounding solutions. Throughout the paper comparison is made between features of the model and properties displayed by biological active transport systems, but there is no claim of an identity between the two.
本文的核心目的是在一个定义明确的系统中阐明与离子主动运输相关的某些现象和概念的含义。为此，对一个主动运输单一离子种类的载体系统的特定模型进行了详细分析和讨论。在该模型中，假设载体介导的离子运输发生在膜上与自由离子移动区域物理分离的区域，膜的主动和被动区域之间通过局部电流流动实现耦合。该模型具有以下特点：(a) 从膜两侧相同的溶液开始，会产生离子的重新分布；(b) 膜两侧溶液相同时，膜上存在电位差，即 “泵” 是生电的；(c) 对称溶液的 “短路” 电流等于中性离子载体复合物的通量；(d) 主动运输速率（进而代谢速率）取决于周围溶液中的离子浓度。在整篇论文中，对该模型的特征与生物主动运输系统所表现出的特性进行了比较，但并未声称两者完全相同。
