What is the main function of aldosterone?

The main function of aldosterone is to facilitate salt and water retention. Aldosterone is a steroid hormone produced by the adrenal glands, and it plays a crucial role in regulating blood pressure and fluid balance within the body. It acts primarily on the kidneys, where it stimulates the reabsorption of sodium ions from the urine back into the bloodstream. As sodium is reabsorbed, water follows due to osmosis, resulting in increased blood volume and, consequently, an increase in blood pressure.

Furthermore, aldosterone promotes the excretion of potassium and hydrogen ions, which helps to maintain electrolyte balance and acid-base homeostasis. This regulation is critical, as proper sodium and potassium levels are vital for normal cellular function and cardiovascular health. In summary, aldosterone's role in facilitating salt and water retention is essential for maintaining blood pressure and overall fluid balance in the body.