Q56 / 200 · MHT CET - Medical 2026 (21 April Shift 1) · Biology
Atrial natriuretic peptide performs all the following functions except -------------------.
- AInhibits $\text{Na}^+$ and Cl- absorption from collecting ducts.
- Correct answerBDecreases excretion of $\text{Na}^+$ in urine.
- CInhibits release of renin.
- DReduces aldosterone and ADH release.
Solution
Atrial natriuretic peptide (ANP) is released by the walls of the atria of the heart in response to an increase in blood volume and pressure.
ANP acts to decrease blood pressure and blood volume by promoting the excretion of $\text{Na}^+$ and water in the urine (natriuresis and diuresis). Therefore, it increases the excretion of $\text{Na}^+$ in urine, rather than decreasing it.
It also inhibits the reabsorption of $\text{Na}^+$ and $\text{Cl}^-$ from the collecting ducts, inhibits the release of renin from the juxtaglomerular apparatus, and reduces the secretion of aldosterone and ADH.
Answer: Decreases excretion of $\text{Na}^+$ in urine.
ANP acts to decrease blood pressure and blood volume by promoting the excretion of $\text{Na}^+$ and water in the urine (natriuresis and diuresis). Therefore, it increases the excretion of $\text{Na}^+$ in urine, rather than decreasing it.
It also inhibits the reabsorption of $\text{Na}^+$ and $\text{Cl}^-$ from the collecting ducts, inhibits the release of renin from the juxtaglomerular apparatus, and reduces the secretion of aldosterone and ADH.
Answer: Decreases excretion of $\text{Na}^+$ in urine.
Hence, the correct answer is option: 'B'.