Ca~(2+) concentration changes in SR during skeletal muscular excitation -contraction coupling

摘要

How is ultrastructural change at millisecond time course in skeletal muscle during coupling after electrical stimulation? What is the relationship between structural change and functional change as excitation-contraction coupling was conducted in skeletal muscle? Though the problems have been studied physiologically for long time, there are still in indistinction. The cause is that the muscular structural change is very fast (millisecond state) during coupling. So it can not be realized that the skeletal muscles are immediately fixed by chemical fixation during coupling. To solve the problems, the ideal method is the freezing fixation and computer technology. We employ a new technology that is the system of a detector with two-way infrared and a computer in order to control the signal ofelectrical stimulation and quick-freezing fixation for structural researches of skeletal muscle during excitation-contraction coupling. The purpose is that skeletal muscle is immediately fixed by quick freezing after electrical stimulation following the known time courses. So it is possible for us to understand the ultrastructural change of skeletal muscle through our tests. We have obtained the ultrastructure and Ca~(2+) concentration changes of skeletal muscle in 0.8 ms and 5.6 ms after electrical stimulation.