Acta Vet. Brno 2006, 75: 183-196

https://doi.org/10.2754/avb200675020183

Ultrashort Bradycardic Effect of Newly Synthesized Compounds

L. Bartošová1, M. Frydrych1, G. Vaculová1, K. Beránková1, M. Bébarová2, R. Opatřilová3, V. Strnadová1, P. Mokrý3, V. Brunclík4, J. Kolevská4, J. Krčmář1, L. Bartošíková1, T. Florian1, J. Nečas1

1Department of Human Pharmacology and Toxicology, Faculty of Veterinary Medicine, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic,
2Department of Physiology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
3Department of Chemical Drugs, Pharmaceutical Faculty, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic,
4Small Animal Clinic, Faculty of Veterinary Medicine, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic

Received July 13, 2005
Accepted March 16, 2006

Changes in the heart rate induced by four different doses of two newly synthesized potential ultrashort-action antagonists of beta adrenergic receptors were tested in 90 male laboratory Wistar rats. The isoprenaline-induced tachycardia model was used. Their effects were compared with those of esmolol. In the second part of the study, approximate electro-physiological measurements were made in vitro to assess the influence of the compounds tested on ion membrane currents in isolated ventricular cardiomyocytes. Both compounds demonstrated significant bradycardic effects in all concentrations tested compared with the control group, but they differed in the time of the onset of their action. Both newly synthesized compounds induced blockade of the fast sodium current (INa) and potassium currents (Ito, IK1, IK,end).