Unmasking the potential of the angiotensin AT2 receptor as a therapeutic target in hypertension in men and women: what we know and what we still need to find out.

Major sex differences exist in the development and progression of hypertension and cardiovascular disease. Prior to menopause, women have lower arterial pressure and, furthermore, are protected from hypertension and cardiovascular disease relative to age-matched men. However, after menopause this cardiovascular protection in women is lost. These sex differences have been linked to sexual dimorphism in the physiological mechanisms that regulate arterial pressure, including the renin-angiotensin system (RAS), which can also impact on the male and female response to different therapeutic approaches. This suggests that antihypertensive regimens need to be tailored according to sex. Newly discovered components of the RAS have emerged in recent years, allowing us to look beyond the classical RAS for novel therapeutic targets for hypertension. In this context, it is now well established that the angiotensin AT2 receptor (AT2 R) elicits depressor and natriuretic effects and that these effects are greater in females due to enhanced AT2 R levels modulated by oestrogen. In light of knowledge that AT2 R expression is regulated by oestrogen and that the prevalence of hypertension and cardiovascular risk is greater in women after menopause, AT2 R agonist therapy may represent an innovative therapeutic approach to treat hypertension. Consequently, understanding how ageing and changes in the sex hormone balance influence the RAS is vital if we are to evaluate the potential of the AT2 R as a therapeutic target in women and also in men.