Stimulation of myocardial contractility by a new cyclic nucleotide analog, 8-(benzylthio)-N6-n-butyladenosine cyclic 3',5'-phosphate (SQ 80122).

The cyclic nucleotide analog, 8-(benzylthio)-N6-n-butyladenosine cyclic 3',5'-phosphate (SQ 80122) increases contractile force of excised cat right ventricular papillary muscle and stimulates myocardial contractility in the anesthetized dog. The inotropic action of this compound is independent of catecholamines and stimulation of beta-adrenergic receptors in the heart.