Rosenberg R L, Hess P, Reeves J P, Smilowitz H, Tsien R W
Science. 1986 Mar 28;231(4745):1564-6. doi: 10.1126/science.2420007.
Electrophysiological recordings were used to analyze single calcium channels in planar lipid bilayers after membranes from bovine cardiac sarcolemmal vesicles had been incorporated into the bilayer. In these cell-free conditions, channels in the bilayer showed unitary barium or calcium conductances, gating kinetics, and pharmacological responses that were similar to dihydropyridine-sensitive calcium channels in intact cells. The open channel current varied in a nonlinear manner with voltage under asymmetric (that is, physiological) ionic conditions. However, with identical solutions on both sides of the bilayer, the current-voltage relation was linear. In matched experiments, calcium channels from skeletal muscle T-tubules differed significantly from cardiac calcium channels in their conductance properties and gating kinetics.
在将牛心肌肌膜囊泡的膜整合到平面脂质双分子层后，利用电生理记录来分析平面脂质双分子层中的单个钙通道。在这些无细胞条件下，双分子层中的通道表现出与完整细胞中对二氢吡啶敏感的钙通道相似的单通道钡或钙电导、门控动力学和药理反应。在不对称（即生理）离子条件下，开放通道电流随电压呈非线性变化。然而，当双分子层两侧的溶液相同时，电流-电压关系是线性的。在配对实验中，骨骼肌T小管的钙通道在电导特性和门控动力学方面与心脏钙通道有显著差异。
