Angiotensin II receptor type 1

Angiotensin II receptor, type 1 or AT1 receptor is an is_associated_with::angiotensin receptor. It has is_associated_with::vasopressor effects and regulates is_associated_with::aldosterone secretion. It is an important effector controlling is_associated_with::blood pressure and volume in the is_associated_with::cardiovascular system. is_associated_with::Angiotensin II receptor antagonists are drugs indicated for is_associated_with::hypertension, is_associated_with::diabetic nephropathy and is_associated_with::congestive heart failure.

It is the best elucidated angiotensin receptor.

Mechanism
The angiotensin receptor is activated by the vasoconstricting peptide angiotensin II. The activated receptor in turn couples to Gq/11 and thus activates phospholipase C and increases the cytosolic Ca2+ concentrations, which in turn triggers cellular responses such as stimulation of is_associated_with::protein kinase C. Activated receptor also inhibits is_associated_with::adenylate cyclase and activates various is_associated_with::tyrosine kinases.

Effects
The AT1 receptor mediates the major cardiovascular effects of angiotensin II. Effects include vasoconstriction, is_associated_with::aldosterone synthesis and secretion, increased is_associated_with::vasopressin secretion, cardiac hypertrophy, augmentation of peripheral noradrenergic activity, vascular is_associated_with::smooth muscle cells proliferation, decreased renal blood flow, renal is_associated_with::renin inhibition, renal tubular is_associated_with::sodium reuptake, modulation of central is_associated_with::sympathetic nervous system activity, cardiac contractility, central osmocontrol and is_associated_with::extracellular matrix formation.

Pathology
The AT1 receptor may play role in the generation of is_associated_with::reperfusion arrhythmias following restoration of blood flow to is_associated_with::ischemic or is_associated_with::infarcted myocardium.

Gene
It was previously thought that a related gene, denoted as AGTR1B, existed; however, it is now believed that there is only one type 1 receptor gene in humans. At least four is_associated_with::transcript variants have been described for this gene. Additional variants have been described but their full-length nature has not been determined. The entire coding sequence is contained in the terminal exon and is present in all transcript variants.

Interactions
Angiotensin II receptor type 1 has been shown to interact with is_associated_with::Zinc finger and BTB domain-containing protein 16. The protein's mRNA has been reported to interact with is_associated_with::Mir-132 microRNA as part of an RNA silencing mechanism that reduces receptor expression.