Angiotensin II/Angiotensin (1–7) ratio and 24-h blood pressure throughout the menstrual cycle and in women using oral contraceptives

BACKGROUND Women using oral contraceptives have higher ambulatory blood pressures (BPs) than other women. We sought to learn whether this was associated with an alteration in the balance of angiotensin II (Ang)/Ang (1-7) and whether this ratio and BP remained constant throughout the menstrual cycle. METHOD In total, 30 (15 ovulatory, 15 taking oral contraceptives) healthy, normotensive women aged 18-30 years were studied. The ovulatory group was assessed within days 1-5 (follicular phase) and 19-23 (luteal phase) and the oral contraceptive group within days 19-23. Peripheral, central and 24-h BP, vascular wall stiffness, and body composition were measured along with plasma estradiol, progesterone, renin, aldosterone, Ang II, and Ang (1-7) concentrations. RESULTS In ovulatory women plasma renin activity (P