Angiotensin II Type 1 Receptor (AT1)

Angiotensin II Type 1 Receptor Overview

The Angiotensin II Type 1 Receptor (AT1) is a key G protein-coupled receptor (GPCR) belonging to the Gq/11 family, playing a crucial role in the renin-angiotensin system (RAS). It is encoded by the AGTR1 gene and exhibits a 7-transmembrane α-helical structure. Activated by angiotensin II, it couples primarily to Gq/11 and Gi/o proteins, triggering signaling cascades including activation of phospholipase C, increase in cytosolic Ca2+, stimulation of protein kinase C, and activation of tyrosine kinases and MAPK/ERK pathways. The AT1 receptor mediates most effects of angiotensin II, such as vasoconstriction, aldosterone secretion, cardiac hypertrophy, and renal sodium reuptake. It is widely distributed in tissues like the heart, blood vessels, kidney, and brain. As an important therapeutic target, its activity is blocked by Angiotensin II Receptor Blockers (ARBs) like losartan, irbesartan, telmisartan, and olmesartan, used to treat hypertension, diabetic nephropathy, heart failure, and vascular diseases. AT1 receptor overexpression is associated with advanced cancer stages, and it contributes to inflammation and atherosclerosis. ARBs have shown anti-inflammatory effects and are considered first-line antihypertensives in specific patient groups.

Mechanism of Action

Angiotensin II receptor blockers (ARBs), also known as AT1 receptor antagonists, selectively block the activation of the AT1 receptor, preventing the binding of angiotensin II.

Biological Functions

Safety Considerations

Interacting Drugs

Associated Biomarkers