Systemic and coronary hemodynamic effects of Abbott (40557) and its interaction with aminophylline

Adenosine is a naturally occurring substance with potent coronary vasodilator action. However, its action is of short duration due to its rapid inactivation in blood and other tissues (1). If used for therapeutic purposes a prolonged duration of action might be desirable. A recent adenosine derivative (Abbott 40557) ethyl-adenosine-5'-carboxylate hydrochloride1) has marked and prolonged coronary vasodilator activity (2,3). The present report concerns the coronary and systemic hemodynamic and metabolic effects of A 40557 and attempts to determine whether, like adenosine, its action is enhanced by dipyridamole (4,5), hexobendine (6), and Cassella 7657 (7) or inhibited by aminophylline (8,9).