title: Comparision of the inotropic effects of levosimendan, rolipram, and dobutamine on human atrial trabeculae.
abstract: The aim of this study was to compare the positive inotropic effects of 3 different agents with 3 different mechanisms of actions-levosimendan, rolipram, and dobutamine-on human atrial trabecular muscles. Samples of right atrial appendage (1 cm, 500-1000 mg) were removed and immersed in preoxygenated and modified Tyrode solution. In oxygenated Tyrode solution, preparations were used to investigate the concentration-effect relationship of levosimendan, dobutamine, and rolipram on percentage developed tension (DT), from 10 to 10 M, each concentration for 15 minutes. All 3 agents produced concentration-dependent increments in DT. We found that levosimendan was the most efficacious positive inotropic agent on isolated human atrial trabeculae. Both the sensitivity (pD2) and maximum response (Emax) of human atrial trabeculae to levosimendan (6.711 +/- 0.26 and 23.2 +/- 2.2 mN, respectively) were significantly greater than those of dobutamine (6.663 +/- 0.19 and 17.6 +/- 2.8 mN) and rolipram (6.497 +/- 0.18 and 15.0 +/- 1.0 mN). pD2 and Emax values for dobutamine were significantly higher than those for rolipram. It was suggested that because of its potential to enhance cardiac performance without predisposition to calcium-induced arrhythmias, levosimendan might be more useful as a positive inotropic agent in clinical practice.
authors.affiliation: Department of Pharmacology, Akdeniz University, Medical Faculty, Antalya, Turkey.
authors.forename: Coskun
authors.initials: C
authors.lastname: Usta
authors.forename: Paolo Emilio
authors.initials: PE
authors.lastname: Puddu
authors.forename: Ugo
authors.initials: U
authors.lastname: Papalia
authors.forename: Vincenzo
authors.initials: V
authors.lastname: De Santis
authors.forename: Domenico
authors.initials: D
authors.lastname: Vitale
authors.forename: Luigi
authors.initials: L
authors.lastname: Tritapepe
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Mazzesi
authors.forename: Fabio
authors.initials: F
authors.lastname: Miraldi
authors.forename: Sadi S
authors.initials: SS
authors.lastname: Ozdem
mesh_terms: D000328:Adult; D000368:Aged; D002316:Cardiotonic Agents / Q000494:pharmacology*; D003324:Coronary Artery Disease / Q000175:diagnosis / Q000601:surgery; D004280:Dobutamine / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004353:Drug Evaluation, Preclinical / Q000379:methods; D004558:Electric Stimulation; D005260:Female; D006325:Heart Atria / Q000187:drug effects* / Q000473:pathology*; D006349:Heart Valve Diseases / Q000175:diagnosis / Q000601:surgery; D006801:Humans; D006835:Hydrazones / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000187:drug effects* / Q000502:physiology; D011724:Pyridazines / Q000494:pharmacology*; D012214:Rheumatic Heart Disease / Q000175:diagnosis / Q000601:surgery; D020889:Rolipram / Q000494:pharmacology*; D000077464:Simendan; D019209:Troponin C / Q000502:physiology
chemical_list: D002316:Cardiotonic Agents; D006835:Hydrazones; D011724:Pyridazines; D019209:Troponin C; D000077464:Simendan; D004280:Dobutamine; D020889:Rolipram