We have recently investigated the effects of short-term ACE2 infusion in human PAH patients, and found reduced oxidant stress and increased plasma superoxide dismutase-2 (SOD2) with ACE2; in parallel, we have found that application of a synthetic agonist for Mas receptor increases SOD2 expression in porcine pulmonary vessels (Carrier et al., 2016). This evidence concerns the gene ACE2 and pulmonary arterial hypertension.