Nasledov G A, Katina I E, Zhitnikova Iu V
Ross Fiziol Zh Im I M Sechenova. 2005 Nov;91(11):1288-98.
The functioning of excitation-contraction coupling during tetanic contraction was investigated on frog skeletal muscle. The effect of the calcium release blocker dantrolene was tested on electrically evoked twitches and tetanic contractions. It was shown that the first: developmental stage of tetanus is inhibited by dantrolene as well as a twitch contraction, and does not influenced by calcium-free medium. This substantiates it as based on "voltage dependent Ca-release" (VDCR) mechanism of activation, when depolarization directly opens the rhyanodin receptor calcium channels. The next stage: the long lasting plateau of tetanic contraction, is directly dependent on external Ca2+ entry and also inhibited by dantrolene, and therefore may be described as "calcium-induced Ca-release" (CICR) activation mechanism. It is proposed that such change in ECC mechanism taking place during tetanic contraction, can occur also in conditions of natural muscle activity, because of its rhythmical nature.
在青蛙骨骼肌上研究了强直收缩期间兴奋-收缩偶联的功能。测试了钙释放阻滞剂丹曲林对电诱发的单收缩和强直收缩的影响。结果表明：破伤风的第一个发育阶段以及单收缩均受丹曲林抑制，且不受无钙培养基影响。这证实其基于“电压依赖性钙释放”（VDCR）激活机制，即去极化直接打开兰尼碱受体钙通道。下一阶段：强直收缩的持久平台期，直接依赖于细胞外Ca2+内流，也受丹曲林抑制，因此可描述为“钙诱导钙释放”（CICR）激活机制。有人提出，强直收缩期间发生的这种兴奋-收缩偶联机制变化，由于其节律性，在自然肌肉活动条件下也可能发生。
