 Nuclear and sarcolemmal KATP channels also contribute to the endurance of and recovery from metabolic stress.In order to conserve energy, sarcKATP open, reducing the duration of the action potential while nucKATP-mediated Ca2+ concentration changes within the nucleus favor the expression of protective protein genes.Cardiac ischemia, while not always immediately lethal, often leads to delayed cardiomyocyte death by necrosis, causing permanent injury to the heart muscle.