Angiotensin type 2 receptor in hypertensive cardiovascular disease.
OBJECTIVE
The renin angiotensin system plays a key role in the development of hypertension-induced cardiovascular remodeling and cardiovascular damage. Angiotensin II (Ang II) exerts its effects by acting on two distinct subtypes of receptor, the angiotensin type 1 receptor (AT1R) and the angiotensin type 2 receptor (AT2R). Whereas AT1R mediates most of the recognized actions of Ang II, it appears that AT2R opposes, in part, the actions mediated by AT1R. As the AT2R is expressed in adult tissues in smaller numbers than AT1R, the actions and cell signaling of AT2R have been less well characterized than those of AT1R.


RESULTS
Current knowledge suggests that AT2R stimulation mediates vasodilation, antigrowth, proapoptotic and antiinflammatory effects. Hence, AT2R can modulate cardiovascular remodeling as well as the progression of atherosclerosis. A protective role of AT2R in the cardiovascular system has been also documented in humans, mainly during chronic AT1R inhibition. Furthermore, a new nonpeptide AT2R agonist has been developed, with potential future therapeutic applications in hypertensive conditions.


CONCLUSIONS
This article reviews the role of AT2R expression signaling and function in the pathogenesis of the functional and structural alterations induced by hypertension on the cardiovascular system.
Clinical and Molecular Medicine Department, Cardiology Unit, Sant'Andrea Hospital, Sapienza University of Rome, Via di Grottarossa 1037/1039, Rome, Italy. savoiac@yahoo.it
Carmine
C
Savoia
Michela
M
D'Agostino
Francesco
F
Lauri
Massimo
M
Volpe
D000818:Animals; D006332:Cardiomegaly / Q000209:etiology; D002318:Cardiovascular Diseases / Q000209:etiology*; D004195:Disease Models, Animal; D006801:Humans; D006973:Hypertension / Q000150:complications*; D009569:Nitric Oxide / Q000096:biosynthesis; D052250:Nitric Oxide Synthase Type III / Q000378:metabolism; D044139:Receptor, Angiotensin, Type 2 / Q000502:physiology*; D014657:Vasculitis / Q000209:etiology; D014664:Vasodilation
D044139:Receptor, Angiotensin, Type 2; D009569:Nitric Oxide; D052250:Nitric Oxide Synthase Type III