Which is the hormone that increases water reabsorption by inserting a water channel or aquaporins?

Correct option is C

Ans (c)
Sol. Angiotensin hormone: Angiotensin II plays a role in regulating blood pressure and fluid balance by causing vasoconstriction and stimulating the release of aldosterone. However, it does not directly insert water channels (aquaporins) into kidney cells to increase water reabsorption.
Aldosterone hormone: Aldosterone regulates sodium and potassium levels in the body, promoting sodium reabsorption and potassium excretion in the kidneys. It indirectly affects water retention but does not involve aquaporins.
Anti-diuretic hormone: Also known as vasopressin, this hormone directly increases water reabsorption in the kidneys by inserting aquaporin-2 water channels into the collecting duct cells. This action reduces water excretion and concentrates urine, making it the correct answer.
Atrial natriuretic peptide hormone: ANP promotes the excretion of sodium and water by the kidneys, reducing blood volume and pressure. It has an opposite effect to that of the anti-diuretic hormone and does not involve aquaporins.