电刺激-冷冻固定法研究兴奋收缩偶联时骨骼肌的超微结构形态变化

Study on Ultrastructural Changes of Skeletal Muscle during Excitation—Contraction Coupling by Electric Stimulation—Freezing Fixation

兴奋－收缩偶联时，肌浆网中的钙离子是通过何种途径被刺激而释放的？偶联发生时其形态变化与其功能变化存在着什么样的关系？这是细胞生物学、生理学几十年来最感兴趣的研究热点之一。由于兴奋－收缩偶联的时间历程极短（以ｍｓ计），现有的化学固定（以ｍｉｎ计）无法保留这瞬间经历时的超微结构形态变化。作者采用计算机控制的超低温快速冷冻固定技术对强直收缩态及完全舒张态的骨骼肌组织进行固定，并采用冷冻置换技术对其处理，因而完全保留了其瞬时变化时的形态结构，对兴奋－收缩偶联发生的瞬间骨骼肌的形态变化进行了探讨。

The ultrastructural changes of skeletal muscle during excitation_contraction coupling were studied using the ultra rapid freezing.The skeletal muscle stimulated were immediately freezing fixed and their ultrastructural changes during excitation_contraction coupling were examined by frecze substitutive electron microscopy.The results show that there is a new system of sarcoplasmic reticulum.There may be a unknown protein in the surface of sarcoplasmic reticulum membrane.