Ischémie-reperfusion et protection cellulaire

Ischemia leads to many conditions faced by intensivists including myocardial infarction, stroke, cardiac arrest or septic shock. Although restoration of blood flow is essential to prevent irreversible cellular injuries, reperfusion per se may dramatically increase tissue damages in excess of that produced by ischemia alone. Recent evidence suggests that the ischemic postconditioning phenomenon, i.e., brief ischemia-reperfusion periods applied on the onset of reperfusion, could prevent lethal reperfusion injuries. Postconditioning activates several primary pathways that inhibit mitochondrial permeability transition pore opening. Pharmacological interventions such as cyclosporin A, a potent permeability transition pore inhibitor, are also able to reduce cell death in numerous ischemia-reperfusion models including myocardial infarction in humans. In the future, ischemic or pharmacological postconditioning might significantly prevent ischemia-reperfusion injuries in our clinical practices.