Question

How does ANP affect the kidneys?

Answer 1

The Atrial Natriuretic Factor (ANP):

1. ANP is a peptide hormone secreted by the cardiac muscle cells in the atria of the heart.
2. It is transcribed by the NPPA gene.
3. It is secreted in response to the increase in blood pressure.
4. It dilates the afferent arterioles (supply blood vessels to the glomerulus) of the glomerulus capsule.
5. Hence, it causes vasodilation.
6. It acts as a check on the Renin-Angiotensin mechanism of the kidney which is responsible for increasing the blood pressure and glomerular filtration rate.
7. ANP helps in suppressing renin (the enzyme which converts angiotensinogen into angiotensin-1) and angiotensin-2 (regulates vasopressin via acting on CNS) for and aldosterone (secreted by adrenal glands to check sodium absorption) to decrease blood pressure.