Which hormone promotes natriuresis?

Natriuresis refers to the excretion of sodium in the urine, and the hormone that specifically promotes this process is Atrial Natriuretic Peptide (ANP). ANP is produced by the heart's atrial cells in response to increased blood volume and pressure. When blood volume rises, ANP is released to help reduce it. This hormone counters the effects of sodium-retaining hormones like aldosterone and angiotensin II by promoting sodium excretion by the kidneys, leading to decreased blood volume and pressure.

In addition to natriuresis, ANP promotes diuresis, which is the increased production of urine. This is beneficial in conditions of fluid overload, as ANP helps to restore balance by facilitating the removal of excess sodium and water from the body, thus reducing the workload on the heart and preventing complications associated with hypertension.

Other hormones, such as aldosterone and angiotensin II, serve to retain sodium and conserve water, thereby increasing blood pressure and volume, which contrasts with the role of ANP. ADH (antidiuretic hormone) functions primarily to promote water reabsorption in the kidneys, not specifically to promote sodium excretion.