Aldo was shown by Edelman (4) to bind to a specific receptor and then be transported into the nucleus of aldo responsive cells and subsequently lead to the production of aldo-induced proteins. The first aldo receptor antagonist )ARA(, spironolactone, has been used clinically for over 30 years in the management of edema and in the past few years a new agent Eplerenone, which is structurally similar to spironolactone, but without the side effect of gynecomastia, has come into clinical use in the USA and in Israel.