Angiotensin receptor

The angiotensin receptors are a class of G-protein coupled receptors with angiotensins as ligands. The AT₁ and AT₂ receptors are ~30% homologous, but have similar affinity to angiotensin II which is their main ligand. They are important in the renin-angiotensin system.

The AT₁ receptor is the best elucidated angiotensin receptor. It is a G-protein coupled receptor which activates phospholipase C and inhibits adenylate cyclase. Effects mediated by the AT₁ receptor include vasoconstriction, aldosterone synthesis and secretion, increased vasopressin secretion, cardiac hypertrophy, augmentation of peripheral noradrenergic activity, vascular smooth muscle cells proliferation, decreased renal blood flow, renal renin inhibition, renal tubular sodium reuptake, modulation of central sympathetic nervous system activity, cardiac contractility, central osmocontrol and extracellular matrix formation.

The AT₂ receptor is a 7TM receptor that is probably a G-protein coupled receptor. Effects mediated by the AT₂ receptor include inhibition of cell growth, fetal tissue development, modulation of extracellular matrix, neuronal regeneration, apoptosis, cellular differentiation and maybe vasodilation.

Other subtypes include AT₃ receptor and AT₄ receptor.

See also:

• Angiotensin II receptor antagonist