Angiotensin

Definition

A peptide hormone produced by the renin-angiotensin system that acts as a potent vasoconstrictor and regulates blood pressure and sodium balance. The most active form is angiotensin II.

How it works

Angiotensin exists in several forms, with angiotensin II being the most biologically active. It is produced through a cascade: renin cleaves angiotensinogen to form angiotensin I, which is then converted to angiotensin II by the angiotensin-converting enzyme (ACE). Angiotensin II directly constricts blood vessels, raising blood pressure, and indirectly increases sodium and water retention by stimulating aldosterone release from the adrenal glands. High levels of circulating angiotensin II are associated with hypertension, particularly in salt-sensitive individuals.

Role

Angiotensin II is a key regulator of blood vessel tone, sodium retention, and blood pressure elevation.

Examples

• ACE inhibitors reducing angiotensin II production
• ARB blockers preventing angiotensin II receptor binding
• Excessive sodium intake increasing angiotensin II activation
• Low sodium diets decreasing angiotensin II levels

Recommendations

Limit sodium intake to reduce angiotensin II activation. If diagnosed with hypertension, discuss ACE inhibitors or ARBs with your healthcare provider. Maintain a balanced electrolyte profile to support natural regulation of the renin-angiotensin system.

Key takeaway

Controlling angiotensin II levels through diet and medication is critical for managing blood pressure.

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