Onset and magnitude of cardiovascular response to dobutamine and AR-L 115 BS, a new positive inotropic agent with additional vasodilating activity, in normal subjects.
2-[(2-Methoxy-4-methylsulfinyl) phenyl]-iH-imidazo[4,5-b]pyridine (AR-L 115 BS), 0.7 mg/kg, was compared to dobutamine, 0.01 mg/kg, and placebo after i.v. administration in a double-blind cross-over study in healthy subjects. The systolic time intervals, the blood pressure and the heart rate were used as a measure of efficacy. Both substances caused a significant reduction in the pre-ejection period (PEP), in the duration of the electromechanical systole (QS2) and in the ratio of the pre-ejection period to the left ventricular ejection time (PEP/LVET). Left ventricular ejection time was reduced only after AR-L 115 BS. The heart rate was slightly increased by AR-L 115 BS and remained unchanged after dobutamine. Both substances caused a small increase in systolic and a small decrease in diastolic blood pressure. The onset of action was immediate after administration of both substances. The duration of action on the systolic time intervals lasted up to 30 min for dobutamine and even longer for AR-L 115 BS, while the effect on the blood pressure and heart rate seemed to be of shorter duration. No serious side effects were reported.
D000328:Adult; D001794:Blood Pressure / Q000187:drug effects; D002316:Cardiotonic Agents / Q000494:pharmacology*; D002395:Catecholamines / Q000494:pharmacology*; D004280:Dobutamine / Q000494:pharmacology*; D004562:Electrocardiography; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D007093:Imidazoles / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged
D002316:Cardiotonic Agents; D002395:Catecholamines; D007093:Imidazoles; D004280:Dobutamine; C029758:sulmazole