They showed that FMD and NID were significantly impaired in patients with APA compared to those in patients with essential hypertension, regardless of the presence or absence of KCNJ5 mutation at baseline, and that FMD and NID were significantly improved in APA patients with KCNJ5 mutation after adrenalectomy, with significant correlations of reductions in plasma aldosterone concentration with improvements in FMD and NID, whereas only NID was improved in APA patients without KCNJ5 mutation after adrenalectomy. The gene discussed is KCNJ5; the disease is essential hypertension.