NOS3 and Hypertension: Although this redox cross talk was initially demonstrated for the NOX2/mitochondrial axis in the setting of hypertension [137,138,139], nitrate tolerance [140], and aging [79,82,139], it can be extended to other ROS-producing enzymes such as uncoupled eNOS [90,139] and xanthine dehydrogenase/oxidase conversion [64,90] (Figure 4) as well as to other disease settings.