A steroid hormone made by the adrenal cortex (the outer layer of the adrenal gland). It helps control the balance of water and salts in the kidney by keeping sodium in and releasing potassium from the body. Too much aldosterone can cause high blood pressure and a build-up of fluid in body tissues. Aldosterone is a type of mineralocorticoid hormone.
Source: NCI Dictionary of Cancer Terms2008-05-28