Normalization of endothelial function by spironolactone (Quaschning et al., 2001) or eplerenone (Quaschning et al., 2001; Sanz-Rosa et al., 2005) through an increase in eNOS protein and the reduction of elevated NADPH oxidase activity was previously observed in several models of hypertension (Harvey et al., 2017). The gene discussed is FMO5; the disease is hypertensive disorder.