Role of mitochondrial permeability transition pore in cardioprotection by remote preconditioning / 中国应用生理学杂志

ABSTRACT

<p><b>AIM</b>To investigate the role of mitochondrial permeability transition pore (MPTP) in the cardioprotection by remote preconditioning (RPC).</p><p><b>METHODS</b>Remote Precondition (RPC) was induced in anesthetized male Sprague-Dawley rats by three cycles of 5 min of right femoral artery occlusion followed by 5 min of reperfusion. Myocardial ischemia/reperfusion (I/R) injury was achieved by ligation of the left anterior descending coronary artery for 30 min and then reperfusion for 120 min. Infarct size was determined by 2,3,5-triphenyltetrazolium chloride (TTC) staining method. The level of lactate dehydragenase (LDH) in plasma and the opening of the mitochondrial permeability transition pore (MPTP) were measured.</p><p><b>RESULTS</b>RPC significantly decreased the infarct size and plasma lactate dehydrogenase level induced by I/R, and these effects were attenuated by atractyloside (Atr, 5 mg/kg), a MPTP activator. However, administration of cyclosporin A (CsA, 10 mg/kg), an inhibitor of MPTP, decreased the effect of I/R. In isolated ventricular myocytes loaded with calcein, RPC decreased the MPTP opening, and this effect was attenuated by Atr (20 micromol/L).</p><p><b>CONCLUSION</b>Inhibition of MPTP opening is involved in the cardioprotection by RPC.</p>