Receptors and their classification:: focus on angiotensin II and the AT2 receptor

Angiotensin II mediates its effects through angiotensin receptors, The use of specific angiotensin receptor ligands and the cloning of these receptors allows their classification. So far, the AT(1), AT(2) and atypical angiotensin II receptors are recognised. The AT(1) receptor is responsible for the classical effects of the renin-angiotensin system such as vasoconstriction, renal salt and water retention, central osmo-control and stimulation of cell growth. The function of the AT(2) receptor is far from clear but this receptor appears to be important in fetal development, cell growth inhibition and differentiation processes. This review describes the angiotensin receptors and focuses on the possible functions of the AT(2) receptor.