SOD2 and cardiomyopathy: SODs convert O2− to H2O2 and there are three isoforms: (1) SOD1, a CuZn-SOD found in the cytoplasm that suppresses scavenging of NO by O2− and regulates angiogenesis and vasomotor tone; (2) SOD2, a mitochondrial Mn-SOD located in the mitochondrial matrix and readily inactivated by peroxynitrite, whose deletion induces perinatal lethality due to cardiomyopathy; and (3) SOD3, secreted and then tethered to the outer plasma membrane, is particularly important in the cardiovascular system due to its high expression in blood vessels, lung and heart [12,17].