Related Experiment Video
Updated: May 26, 2026
11:20
Imaging of Intracellular ATP in Organotypic Tissue Slices of the Mouse Brain using the FRET-based Sensor ATeam1.03YEMK
Published on: December 19, 2019
Selective ion changes during spontaneous mitochondrial transients in intact astrocytes
Guillaume Azarias1, Jean-Yves Chatton
1Department of Cell Biology and Morphology, University of Lausanne, Lausanne, Switzerland.
Plos One
|December 7, 2011
Summary
Mitochondria undergo spontaneous ionic changes during cellular energy shifts. These transients involve sodium, pH, and reactive oxygen species, potentially driven by localized ATP increases, impacting cellular bioenergetics.
Area of Science:
- Cellular bioenergetics
- Mitochondrial physiology
- Cellular signaling
Background:
- Cellular energy status relies on cytosolic enzymes and mitochondrial ATP production.
- Mitochondria adjust ionic composition to meet cellular energy demands.
- Previous work identified spontaneous mitochondrial sodium (Na+) transients in astrocytes.
Purpose of the Study:
- To investigate the involvement of other ionic species during spontaneous mitochondrial transients.
- To elucidate the sequential events and molecular mechanisms underlying these mitochondrial transients.
Main Methods:
- Utilized multiparameter fluorescence imaging in intact resting astrocytes.
- Combined widefield and total internal reflection fluorescence imaging techniques.
- Monitored mitochondrial Na+, electrical potential, matrix pH, reactive oxygen species, and Ca2+ concentrations.
Main Results:
- Observed coincident changes in mitochondrial Na+, electrical potential, matrix pH, and reactive oxygen species during transients.
- Found no detectable changes in mitochondrial Ca2+ concentration.
- Detected localized, transient decreases in free Mg2+ concentration correlating with Na+ spikes, suggesting local ATP enrichment.
Conclusions:
- Proposed a sequential model for mitochondrial transients initiated by a localized ATP microdomain.
- This microdomain triggers Na+-mediated mitochondrial depolarization, enhancing respiratory chain activity.
- The findings provide a model for ionic communication between the cytosol and mitochondria.
