Mechanism of Action of Angiotensin II Type- 1 (AT1) Receptor Blockers


Angiotensin II receptor blockers (ARBs) are a class of medications that work by blocking the effects of angiotensin II, a powerful hormone that constricts blood vessels and raises blood pressure. 

ARBs do this by binding to and blocking the angiotensin II type 1 receptor (AT1 receptor), which is found in many tissues throughout the body, including the heart, blood vessels, and kidneys.

When angiotensin II binds to the AT1 receptor, it causes a number of effects, including:
  • Vasoconstriction (narrowing of blood vessels)
  • Aldosterone release (a hormone that causes the kidneys to retain sodium and water)
  • Catecholamine release (adrenaline and noradrenaline, which also raise blood pressure)
  • Hypertrophic response (thickening of the heart muscle)

By blocking the AT1 receptor, ARBs prevent these effects from occurring, which leads to a lowering of blood pressure. 





ARBs are also known to have other beneficial effects, such as reducing inflammation and protecting the heart and kidneys from damage.

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