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Updated: Jun 12, 2026
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Assessment of Myofilament Ca2+ Sensitivity Underlying Cardiac Excitation-contraction Coupling
Published on: August 1, 2016
Do rat cardiac myocytes release ATP on contraction?
Stefanie Gödecke1, Thomas Stumpe, Hilmar Schiller
1Institut für Herz- und Kreislaufphysiologie, Heinrich-Heine-Universität, Düsseldorf, Germany. stefanie.goedecke@uni-duesseldorf.de
American Journal of Physiology. Cell Physiology
|May 6, 2005
Summary
Mechanical strain on contracting heart cells does not release ATP. Researchers used sensitive methods to detect ATP release from cardiomyocytes but found none, indicating mechanical force alone is not a key stimulus for ATP release.
Area of Science:
- Cardiovascular Biology
- Cellular Physiology
- Biochemistry
Background:
- Adenosine triphosphate (ATP) is released by cells under mechanical stress, acting as a signaling molecule.
- The role of mechanical forces on cardiomyocyte membranes in stimulating ATP release remains unclear.
Purpose of the Study:
- To investigate if mechanical forces on contracting cardiomyocytes stimulate ATP release.
- To determine if cardiomyocyte contraction during longitudinal shortening releases ATP.
Main Methods:
- Assayed ATP release from electrically stimulated adult rat cardiomyocytes and ES cell-derived mouse cardiomyocytes using luciferase and a sensitive CCD camera.
- Utilized membrane-bound luciferase targeted to the sarcolemma for enhanced detection sensitivity.
- Validated detection method with shear stress-induced ATP release from endothelial cells.
Main Results:
- No significant ATP release was detected from contracting adult rat or ES cell-derived mouse cardiomyocytes.
- Measurable ATP release was only observed in damaged or permeabilized cells.
- The sensitive detection system, validated with endothelial cells, did not detect ATP release from single contracting cardiomyocytes.
Conclusions:
- Mechanical deformation of cardiomyocytes during contraction does not appear to be a primary stimulus for cellular ATP release.
- The study provides evidence against mechanical strain as a key trigger for ATP release in cardiomyocytes.
- The sensitive detection methodology is effective for other cell types under mechanical stress.
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