Schumaker M F, MacKinnon R
Department of Chemistry, Brandeis University, Waltham, Massachusetts 02254.
Biophys J. 1990 Oct;58(4):975-84. doi: 10.1016/S0006-3495(90)82442-5.
Recent experimental evidence suggests that certain membrane channels operate in a nearly ion-saturated state. We therefore consider a "single-vacancy" model of ion permeation: if a channel has n conducting sites, it will contain either n or n-1 ions. Simple analytical expressions for the current, conductance, and reversal potential under bi-ionic conditions are derived. The results are compared with those of single ion models and recent experiments on Ca2(+)-activated K+ channels.
最近的实验证据表明，某些膜通道在几乎离子饱和的状态下运作。因此，我们考虑离子渗透的“单空位”模型：如果一个通道有n个传导位点，它将包含n个或n - 1个离子。推导了双离子条件下电流、电导和反转电位的简单解析表达式。将结果与单离子模型的结果以及最近关于Ca2(+)激活的K+通道的实验结果进行了比较。
