As illustrated in Figure 3, this reaction of the endothelial cell involving the L-arg-eNOS system also generates ROS, including the free radicals (unpaired electrons) superoxide anions (•O2-), peroxynitrite (•ONOO-), and hydroxyl radicals (OH•O) and non-radicals, such as hydrogen peroxide (H2O2), that are involved in diverse cardiovascular diseases [46-50]. This evidence concerns the gene NOS3 and cardiovascular disorder.