Compugen has identified an alternative splicing event in the gene that codes for the protein precursor of two natriuretic peptide hormones: atrial natriuretic peptide (ANP) and Urodilatin. These two peptide hormones are secreted by the heart and kidney, respectively, to decrease blood pressure and to increase water and salt excretion. While ANP and another member of the natriuretic peptide hormone family, BNP, are clinically available for the treatment of acute congestive heart failure; and, Urodilatin is still in clinical development. Two forms of CGEN-34, based on the N-terminal differences between ANP and Urodilatin were analyzed. The biological activity of these two CGEN-34 variant forms has been demonstrated both in vitro and in vivo. Both variants have shown activation of the ANP cell receptor in rat lung membranes, and have also shown significant cardiovascular and renal effects in rats, including lowering blood pressure and heart rate, as well as increasing urine volume and sodium excretion. The significant effects exerted by these variants on hemodynamic and renal parameters in vivo support their potential use as therapeutic agents for cardiac and renal indications.