Ventricular fibrillation in preconditioned pig hearts: role of KATP
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چکیده
Rioufol, Gilles, Michel Ovize, Joseph Loufoua, Calin Pop, Xavier André-Fouët, and Yves Minaire. Ventricular fibrillation in preconditioned pig hearts: role of KATP 1 channels. Am. J. Physiol. 273 (Heart Circ. Physiol. 42): H2804– H2810, 1997.—ATP-dependent potassium (KATP 1 ) channels play a role in the infarct size-limiting effect of preconditioning in pigs. We previously demonstrated that preconditioning shortens monophasic action potential duration (MAPD) and accelerates the time to ventricular fibrillation (VF) during a prolonged ischemia in pigs. We sought to determine whether the mechanism of the reduced time to VF in preconditioned pigs is a consequence of KATP 1 channel activation. Pigs underwent 40 min of coronary occlusion and 2 h of reperfusion. Before this, animals received either no intervention (control), 10 min of ischemia and 10 min of reperfusion (preconditioned), or an intravenous infusion of nicorandil, a KATP 1
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Clinical/Translational Research Role of KATP Channels in the Maintenance of Ventricular Fibrillation in Cardiomyopathic Human Hearts
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