The primary role of aldosterone is

Aldosterone

• Aldosterone, a steroid hormone secreted by the adrenal glands.
• Aldosterone serves as the principal regulator of the salt and water balance of the body and thus is categorized as a mineralocorticoid.
• It also has a small effect on the metabolism of fats, carbohydrates, and proteins.
• Aldosterone’s primary function is to act on the late distal tubule and collecting duct of nephrons in the kidney, directly impacting sodium absorption and potassium excretion.
• It also indirectly affects the excretion of hydrogen ions by changing the amount of potassium in the lumen of the nephron, causing downstream consequences on alpha-intercalated cells.
• It affects blood pressure by regulating the amount of sodium (and the chloride that diffuses with sodium across the membranes) by increasing or decreasing the total amount of volume in the extracellular fluid (ECF).
• This is not to be confused with the effect of anti-diuretic hormone (ADH). ADH is often released simultaneously with aldosterone.
• This allows for blood pressure control by causing the release and fusion of aquaporin channels into the membrane of the principal cells. Water will then be reabsorbed into the ECF.
• Together these two hormones can cause an increase in the amount of water taken up through the nephron, therefore increasing blood pressure.