Which corticosteroid is primarily classified as a mineralocorticoid?

The corticosteroid primarily classified as a mineralocorticoid is aldosterone. Mineralocorticoids are a class of corticosteroids that play a crucial role in the regulation of electrolyte and water balance, primarily by promoting sodium retention in the kidneys, which influences blood volume and blood pressure.

Aldosterone is produced in the adrenal cortex and is the principal mineralocorticoid. Its main function is to increase the reabsorption of sodium and the excretion of potassium by the nephrons in the kidneys, thus contributing significantly to the regulation of mineral balance and electrolyte homeostasis in the body.

Other corticosteroids mentioned, such as corticosterone, cortisol, and cortisone, are classified mainly as glucocorticoids, which are primarily involved in the regulation of metabolism and the immune response. Although corticosterone has some minor mineralocorticoid activity, it is not as prominent or as significant in that role compared to aldosterone. Cortisol and cortisone primarily function to regulate glucose metabolism and mediate stress responses, further highlighting why aldosterone is the primary mineralocorticoid.