EHNA acts as an inhibitor of adenosine deaminase (ADA) and as a selective inhibitor of cyclic nucleotide phosphodiesterase- 2 (PDE2). EHNA has been used to investigate the protective response of adenosine in myocardial cell studies in vitro, and to understand the role that the adenosine pathway plays in heart studies. Urinary bladder studies in vitro show that EHNA blocks the ATPase and motor activities of cytoplasmic dynein in vitro and cardiac myocyte studies show EHNA to block the activity of cGMP-stimulated phosphodiesterase.