Angiotensin receptor

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angiotensin II receptor, type 1
Identifiers
Symbol	AGTR1 AGTR1B
HUGO	336
Entrez	185
OMIM	106165
RefSeq	NM_000685
UniProt	P30556
Other data
Locus	Chr. 3 q21-q25

angiotensin II receptor, type 2
Identifiers
Symbol	AGTR2
HUGO	338
Entrez	186
OMIM	300034
RefSeq	NM_000686
UniProt	P50052
Other data
Locus	Chr. X q22-q23

The angiotensin receptors are a class of G protein-coupled receptors with angiotensins as ligands. They are important in the renin-angiotensin system: they are responsible for the signal transduction of the main effector hormone.

1 Structure
2 Members
3 See also
4 External links

The AT₁ and AT₂ receptors share a sequence identity of ~30%, but have a similar affinity for angiotensin II, which is their main ligand.

The AT₁ receptor is the best elucidated angiotensin receptor. It is coupled to phospholipase C and angiotensin II increases the cytosolic Ca²⁺ level. It also inhibits adenylate cyclase and activate various tyrosine kinases. 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.

AT₂ receptors are more plentiful in the fetus and neonate. 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 poorly characterized subtypes include the AT₃ and AT₄ receptors. The AT₄ receptor is activated by the angiotensin II metabolite angiotensin IV, and may play a role in regulation of the CNS extracellular matrix.