Which hormone increases blood pressure by vasoconstriction and stimulating aldosterone release?

Which hormone increases blood pressure by vasoconstriction and stimulating aldosterone release?

• A. Angiotensin II
• B. Atrial natriuretic peptide
• C. Antidiuretic hormone
• D. Cortisol

Answer: (A)

Angiotensin II drives blood pressure up through two complementary actions: it causes vasoconstriction of arterioles, raising total peripheral resistance, and it stimulates the adrenal cortex to release aldosterone, which increases sodium (and water) reabsorption in the distal nephron, expanding blood volume. This hormone is a key effector of the renin–angiotensin–aldosterone system, formed when renin (from the kidney) converts angiotensinogen (from the liver) to angiotensin I, which is then converted to angiotensin II by ACE. Aldosterone raises BP by increasing sodium reabsorption, which pulls water along and increases circulating volume. Other options don’t fit as well: atrial natriuretic peptide lowers BP by promoting natriuresis and vasodilation; antidiuretic hormone mainly conserves water (with some vasoconstriction at high levels but no direct aldosterone release); cortisol influences BP indirectly but does not directly stimulate aldosterone release.

Angiotensin II drives blood pressure up through two complementary actions: it causes vasoconstriction of arterioles, raising total peripheral resistance, and it stimulates the adrenal cortex to release aldosterone, which increases sodium (and water) reabsorption in the distal nephron, expanding blood volume. This hormone is a key effector of the renin–angiotensin–aldosterone system, formed when renin (from the kidney) converts angiotensinogen (from the liver) to angiotensin I, which is then converted to angiotensin II by ACE. Aldosterone raises BP by increasing sodium reabsorption, which pulls water along and increases circulating volume.

Other options don’t fit as well: atrial natriuretic peptide lowers BP by promoting natriuresis and vasodilation; antidiuretic hormone mainly conserves water (with some vasoconstriction at high levels but no direct aldosterone release); cortisol influences BP indirectly but does not directly stimulate aldosterone release.