Our novel data indicates that (1) SRD sex specifically increases aldosterone production in association with an increase in adrenal CYP11B2 and ATR expression, (2) sodium restriction impairs endothelial function in female mice, ablating the baseline sex difference, via reductions in NO bioavailability, (3) sodium restriction increases vascular contractility in female mice, ablating baseline sex differences, and (4) endothelial MR deletion (KO) protects female mice from SRD-induced endothelial dysfunction and increased vascular contractility. The gene discussed is ATR; the disease is endothelial dysfunction.