Eisenberg R S
Can J Physiol Pharmacol. 1987 Apr;65(4):686-90. doi: 10.1139/y87-113.
Every eukaryotic cell contains systems linking the extracellular space and internal membrane compartments. These systems allow cells to communicate and, ultimately they allow the nervous system to control most of the cytoplasmic activity. In skeletal muscle, this system is called "excitation-contraction coupling." While much is known of the early and late steps in coupling, the critical link between the cell (i.e., here the T system) membrane and sarcoplasmic reticulum membrane is not known. Electrical coupling cannot easily account for experimental results; here we show that the Ca2+ influx is not causally related to the excitation-contraction coupling. The most likely mechanism seems to be a variant of the "remote control model" in which a voltage change and accompanying charge movement in the T membrane activates an enzyme tethered to the cytoplasmic leaflet of the T membrane but spanning part of the T--sarcoplasmic reticulum gap.
每个真核细胞都包含连接细胞外空间和内膜区室的系统。这些系统使细胞能够进行通讯，最终使神经系统能够控制大部分细胞质活动。在骨骼肌中，这个系统被称为“兴奋 - 收缩偶联”。虽然我们对偶联的早期和晚期步骤了解很多，但细胞（即这里的T系统）膜与肌浆网膜之间的关键联系尚不清楚。电偶联难以轻易解释实验结果；在这里我们表明，Ca2+内流与兴奋 - 收缩偶联没有因果关系。最可能的机制似乎是“遥控模型”的一种变体，其中T膜中的电压变化和伴随的电荷移动激活了一种附着在T膜细胞质小叶但跨越部分T - 肌浆网间隙的酶。
