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Updated: Apr 15, 2026
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Assessment of Sarcoplasmic Reticulum Calcium Reserve and Intracellular Diastolic Calcium Removal in Isolated Ventricular Cardiomyocytes
Published on: September 18, 2017
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Characterizing the trigger for sarcoplasmic reticulum Ca2+ release in cardiac myocytes
Virginie Bito1, Niall Macquaide1, Karin R Sipido1
1Division of Experimental Cardiology, Department of Cardiovascular Sciences, KU Leuven, Belgium.
Cold Spring Harbor Protocols
|April 3, 2015
Summary
This study presents a method to measure L-type calcium current (ICaL) and sarcoplasmic reticulum calcium release. This approach helps evaluate excitation-contraction coupling gain in cardiac function.
Area of Science:
- Cardiology
- Molecular Biology
- Physiology
Background:
- L-type calcium current (ICaL) is crucial for triggering calcium release from the sarcoplasmic reticulum.
- Understanding the relationship between ICaL and calcium release is key to cardiac function.
- Excitation-contraction coupling gain is a critical parameter in cardiac electrophysiology.
Purpose of the Study:
- To describe a novel method for characterizing ICaL and its role in sarcoplasmic reticulum calcium release.
- To establish a protocol for measuring ICaL amplitude, voltage dependence, and associated calcium transients.
- To provide a framework for evaluating excitation-contraction coupling gain.
Main Methods:
- Utilized electrophysiological techniques to isolate and measure ICaL.
- Employed specific internal and external solutions and voltage control to eliminate interfering ionic currents.
- Correlated ICaL measurements with intracellular calcium ([Ca2+]i) transients.
Main Results:
- Successfully characterized ICaL amplitude and voltage dependence.
- Established a method to measure SR calcium release triggered by ICaL.
- Demonstrated a correlation between ICaL and [Ca2+]i transients as an initial assessment of coupling gain.
Conclusions:
- The described method provides a robust approach for assessing ICaL and SR calcium release.
- The relationship between ICaL and [Ca2+]i transients offers a preliminary evaluation of excitation-contraction coupling gain.
- Further investigation involving SR calcium content measurement is recommended for a comprehensive gain analysis.
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