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Assessment of Myofilament Ca2+ Sensitivity Underlying Cardiac Excitation-contraction Coupling
Published on: August 1, 2016
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Ca handling during excitation-contraction coupling in heart failure
Aleksey V Zima1, Elisa Bovo, Stefan R Mazurek
1Department of Cell and Molecular Physiology, Loyola University Chicago, Stritch School of Medicine, 2160 South First Avenue, Maywood, IL, 60153, USA, AZIMA@lumc.edu.
Pflugers Archiv : European Journal of Physiology
|February 12, 2014
Summary
Dysfunctional calcium (Ca) handling in heart failure involves altered ryanodine receptor (RyR) and SR Ca ATPase (SERCA) proteins. These changes disrupt excitation-contraction coupling, impacting heart function and rhythm.
Area of Science:
- Cardiology
- Molecular Biology
- Physiology
Background:
- Excitation-contraction coupling in the heart relies on precise calcium (Ca) cycling.
- The sarcoplasmic reticulum (SR) network and T-tubular system orchestrate Ca release and uptake.
- Dysfunction of key Ca handling proteins, ryanodine receptor (RyR) and SR Ca ATPase (SERCA), is central to heart failure (HF).
Purpose of the Study:
- To review structural modifications of RyR and SERCA in the failing heart.
- To elucidate how these molecular changes impact SR Ca regulation.
- To understand the effects on excitation-contraction coupling in heart failure.
Main Methods:
- Literature review focusing on molecular and cellular mechanisms.
- Analysis of structural changes in RyR and SERCA proteins.
- Examination of Ca cycling abnormalities in heart failure models.
Main Results:
- Heart failure is characterized by widespread Ca regulation abnormalities.
- Altered RyR and SERCA function contribute to impaired Ca release, uptake, and diastolic leak.
- These molecular changes directly affect cardiac contractility and arrhythmogenesis.
Conclusions:
- Modifications in RyR and SERCA structure are critical in heart failure pathophysiology.
- Understanding these molecular alterations is key to addressing abnormal Ca homeostasis.
- Targeting RyR and SERCA may offer therapeutic strategies for heart failure.
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