[The effect of AR-L 115 BS on contractility dynamics of the isolated, metabolically supported dog heart (author's transl)].

In this study the contractility dynamics of the left ventricle are analysed independent of respiration, pre- and afterload, heart rate and perfusion pressure. These parameters alter varyingly following the administration of 2-[(2-methoxy-4-methylsufinyl)phenyl]-1H-imidazo[4,5-b]pyridine (AR-L 115 BS) so that the study plan selected must take these factors into account. The model employed consisted of a metabolically supported isolated pulsating dog's heart. The dose of AR-L 115 Bs used was 0.125 mg/kg body weight and it was infused over a period of 30 min. Altogether the study demonstrates that AR-L 115 BS has a marked positive inotropic effect on the isolated heart even under the conditions of infusion. The coronary resistance diminishes and the cardiac output increases.