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Updated: Aug 10, 2026

Ex Vivo Assessment of Contractility, Fatigability and Alternans in Isolated Skeletal Muscles
Published on: November 1, 2012
[Calcium release during contraction and changes in optical anisotropy in skeletal muscle cells]
1Centra fyziologických vied SAV v Bratislave.
Abstract:
The change in optical anisotropy of the isolated twitch muscle fiber of the frog was analyzed under voltage clamp conditions in fixation of tension. The signal was found to consist of two distinguishable components, i.e. a virtually linear and a nonlinear. The linear part is presumably associated with the activation of Ca-ATPase in the membranes of the sarcoplasmic reticulum. On the basis of a simple model the authors demonstrated that the optical signal which reflects this process can have a practically linear course.
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