Aldosterone is a naturally occuring hormone produced by the adrenal glands. It assists with the regulation of blood pressure. Aldosterone binds to receptors in the kidneys, decreasing the amount of water that passes while encouraging the passage of potassium but not the passage of sodium. This causes a rise in blood pressure as the retained water increases blood volume. Abnormal secretion of aldosterone causes diseases in the kidneys, heart and blood vessels. Aldosterone was first isolated in 1953 by Sylvia and James Tait.