Mineralocorticoids

Removal of the adrenal glands can lead to death within just a few days. Observation of such a unfortunate subject would reveal several key derangements:the concentration of potassium in extracelluar fluid becomes dramatically elevated urinary excretion of sodium is high and the concentration of sodium in extracellular fluid decreases significantly volume of extracellular fluid and blood decrease the heart begins to function poorly, cardiac output declines and shock ensues These phenomena are a direct result of loss of mineralocorticoid activity, and can largely be prevented by replacement of salts and mineralocorticoids. Clearly mineralocorticoids are acutely critical for maintenance of life The principal steroid with mineralocorticoid activity is aldosterone. Cortisol, the major glucocorticoid in non-rodent species, is said to have "weak mineralocorticoid activity", which is of some importance because cortisol is secreted very much more abundantly than aldosterone. Another way to state this is that a small fraction of the mineralocorticoid response in the body is due to cortisol rather than aldosterone.