Olmesartan (RNH-6270) is an angiotensin II receptor (AT1R) antagonist used to treat high blood pressure^[1][2]. In Vitro: Olmesartan (0.7-5 mM; 24, 48 and 72 h) inhibits the growth of HeLa cells as a concentration- and time-dependent mode^[3]. In Vivo: Repeated dosing of olmesartan (1 mg/kg, 2 mg/kg, p.o.) dose-dependently decreases mean arterial blood pressure (MAP) in SHR without significant influence on body weight and food intake during 10 weeks^[1]. Olmesartan (5 mg/kg/d, p.o.) and Hyd treatments lower systolic blood pressure to the same degree in mice. Olmesartan treatment inhibits cardiac hypertrophy, evaluated by echocardiography, heart weight, cross-sectional area of cardiomyocytes, and gene expression. Olmesartan treatment reverses decreased gene expressions of ACE2 and Mas receptor of Ren-Tg mice and inhibits enhanced NADPH oxidase (Nox)4 expression and reactive oxygen species^[2].