Receptor for angiotensin II, a vasoconstricting peptide, which acts as a key regulator of blood pressure and sodium retention by the kidney. The activated receptor in turn couples to G-alpha proteins G(q) (GNAQ, GNA11, GNA14 or GNA15) and thus activates phospholipase C and increases the cytosolic Ca(2+) concentrations, which in turn triggers cellular responses such as stimulation of protein kinase C. Interacts with MAS1 (By similarity). Interacts with ARRB1 (By similarity). Interacts with FLNA (via filamin repeat 21); increases PKA-mediated phosphorylation of FLNA (By similarity). Is expressed in the liver, kidney, aorta, lung, uterus, ovary, spleen, heart, and vascular smooth muscle cell. Expressed most abundantly in the adrenal gland. C-terminal Ser or Thr residues may be phosphorylated. Belongs to the G-protein coupled receptor 1 family.