Abstract
Reperfusion may induce additional cell death in patients with acute myocardial infarction receiving primary angioplasty or thrombolysis. Altered intracellular Ca 2+ handling was initially considered an essential mechanism of reperfusion-induced cardiomyocyte death. However, more recent studies have demonstrated the importance of Ca 2+-independent mechanisms that converge on mitochondrial permeability transition (MPT) and are shared by cardiomyocytes and other cell types. This article analyses the importance of Ca 2+-dependent cell death in light of these new observations. Altered Ca 2+ handling includes increased cytosolic Ca 2+ levels, leading to activation of calpain-mediated proteolysis and sarcoplasmic reticulum-driven oscillations; this can induce hypercontracture, but also MPT due to the privileged Ca 2+ transfer between sarcoplasmic reticulum and mitochondria through cytosolic Ca 2+ microdomains. In the opposite direction, permeability transition can worsen altered Ca 2+ handling and favour hypercontracture. Ca 2+ appears to play an important role in cell death during the initial minutes of reperfusion, particularly after brief periods of ischaemia. Developing effective and safe treatments to prevent Ca 2+-mediated cardiomyocyte death in patients with transient ischaemia, by targeting Ca 2+ influx, intracellular Ca 2+ handling, or Ca 2+-induced cell death effectors, is an unmet challenge with important therapeutic implications and large potential clinical impact. © 2011 The Author.
Original language | English |
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Pages (from-to) | 168-180 |
Journal | Cardiovascular Research |
Volume | 94 |
Issue number | 2 |
DOIs | |
Publication status | Published - 1 May 2012 |
Keywords
- Calpain
- Mitochondria
- Myocardial infarction
- Reperfusion injury