Real-time imaging of apoptotic cell-membrane changes at the single-cell level in the beating murine heart

Nat Med. 2001 Dec;7(12):1352-5. doi: 10.1038/nm1201-1352.


We report a novel real-time imaging model to visualize apoptotic membrane changes of single cardiomyocytes in the injured heart of the living mouse, using fluorescent labeled annexin-V. Annexin-V binds to externalized phosphatidylserine (PS) of cells undergoing programmed cell death. With high-magnification (x100-160) real-time imaging, we visualized the binding of annexin-V to single cardiomyocytes. Kinetic studies at the single-cell level revealed that cardiomyocytes started to bind annexin-V within minutes after reperfusion, following an ischemic period of 30 minutes. The amount of bound annexin-V increased rapidly and reached a maximum within 20-25 minutes. Caspase inhibitors decreased the number of annexin-V-positive cardiomyocytes and slowed down the rate of PS exposure of cardiomyocytes that still bound annexin-V. This technology to study cell biology in the natural environment will enhance knowledge of intracellular signaling pathways relevant for cell-death regulation and strategies to manipulate these pathways for therapeutic effect.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Annexin A5 / metabolism*
  • Apoptosis*
  • Cell Membrane / pathology*
  • Fluorescent Dyes / metabolism
  • Image Processing, Computer-Assisted / instrumentation
  • Image Processing, Computer-Assisted / methods*
  • Kinetics
  • Mice
  • Microscopy, Fluorescence / instrumentation
  • Microscopy, Fluorescence / methods*
  • Myocardial Reperfusion Injury / pathology*
  • Myocardium / pathology*
  • Protein Binding


  • Annexin A5
  • Fluorescent Dyes