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Updated: Aug 6, 2026
14:02
Ex Vivo Assessment of Contractility, Fatigability and Alternans in Isolated Skeletal Muscles
Published on: November 1, 2012
Excitation-contraction coupling from the 1950s into the new millennium
1Division of Molecular Bioscience, John Curtin School of Medical Research, Australian National University, Australian Capital Territory, Australia. angela.dulhunty@anu.edu.au
Clinical and Experimental Pharmacology & Physiology
|August 23, 2006
Summary
Excitation-contraction coupling in muscle relies on a protein complex linking surface depolarization to calcium release. Differences in signaling mechanisms exist between cardiac and skeletal muscle, with ongoing research into protein interactions.
Area of Science:
- Muscle Physiology
- Molecular Biology
- Biochemistry
Background:
- Excitation-contraction coupling (ECC) links muscle membrane depolarization to contraction.
- ECC is mediated by a macromolecular protein complex, the 'calcium release unit' (CRU).
Observation:
- The CRU spans the transverse tubule and sarcoplasmic reticulum membranes.
- Key components include the ryanodine receptor (calcium release channel), an L-type calcium channel (voltage sensor), and calsequestrin.
Findings:
- The CRU integrates surface depolarization with intracellular calcium levels.
- While CRU components are conserved, ECC mechanisms differ: cardiac ECC is calcium-triggered, while skeletal muscle ECC involves conformational coupling.
Implications:
- Understanding ECC has evolved significantly over 50 years.
- Further research is needed to elucidate protein interactions and structures within the CRU for future therapeutic targets.
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