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Updated: Aug 18, 2026

Ex Vivo Assessment of Contractility, Fatigability and Alternans in Isolated Skeletal Muscles
Published on: November 1, 2012
Molecular aspects of the excitation-contraction coupling in skeletal muscle
1Department of Pharmacology, Graduate School of Medicine, The University of Tokyo. iino@m.u-tokyo.ac.jp.
Abstract:
Extremely rapid and massive release of Ca(2+) from the sarcoplasmic reticulum upon depolarization of the T-tubule regulates the contraction of skeletal muscle. The dihydropyridine receptor (voltage sensor) on the T-tubule faces the ryanodine receptor (Ca(2+) release channel) on the sarcoplasmic reticulum at the triadic junction and their intermolecular interaction is responsible for the swift release of Ca(2+) from the sarcoplasmic reticulum. We are now beginning to gain insight into the molecular structures that are important for the coupling mechanism.
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