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Updated: Aug 21, 2026

A Flow Cytometry-based Assay for Measuring Mitochondrial Membrane Potential in Cardiac Myocytes After Hypoxia/Reoxygenation
07:14

A Flow Cytometry-based Assay for Measuring Mitochondrial Membrane Potential in Cardiac Myocytes After Hypoxia/Reoxygenation

Published on: July 13, 2018

Initiation of mitochondrial-mediated apoptosis during cardiac reperfusion

Kathleen Corrigan Lundberg1, Luke I Szweda

  • 1Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH 44106-4907, USA.

Archives of Biochemistry and Biophysics
|November 3, 2004
PubMed

Insights

Cardiac ischemia/reperfusion triggers programmed cell death via the mitochondrial apoptosis pathway. This study confirms that cytochrome c release and apoptosome formation occur in vivo during reperfusion, initiating cardiac cell apoptosis.

Area of Science:

  • Cardiovascular Biology
  • Cell Death Mechanisms
  • Molecular Cardiology

Background:

  • Reperfusion following myocardial ischemia can induce programmed cell death (apoptosis).
  • Mechanisms of in vivo cardiac apoptosis during ischemia/reperfusion are not fully understood.
  • Mitochondrial-mediated apoptosis is a key pathway in cell death.

Purpose of the Study:

  • To investigate if mitochondrial-mediated apoptosis is initiated in vivo during cardiac ischemia/reperfusion.
  • To elucidate the specific molecular events involved in this process.

Main Methods:

  • Assessing cytochrome c levels in cytosolic and mitochondrial fractions.
  • Analyzing the expression and localization of the pro-apoptotic protein Bax.
  • Detecting the formation of high molecular weight cytochrome c oligomers (apoptosome).
  • Quantifying pro-caspase-9 levels during reperfusion.

Main Results:

  • Cytochrome c levels increased in the cytosol exclusively during reperfusion.
  • Bax disappeared from the cytosol and appeared in the mitochondrial fraction.
  • High molecular weight cytochrome c oligomers, indicative of apoptosome formation, were detected.
  • Pro-caspase-9 levels decreased exclusively during reperfusion.

Conclusions:

  • The mitochondrial-mediated pathway of apoptosis is activated in vivo during cardiac ischemia/reperfusion.
  • These findings identify key molecular players and events in the initiation of cardiac cell death post-ischemia.

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