The project introduces anesthetised guinea pig as a model for arrhythmogeneicity testing of TP-1, new drug with potential beta adrenergic action. As whole body model, it allows to evaluate complex reaction of cardiovascular system to tested drug. From ECG, RR intervals, corrected QT intervals and incidence of ventricular arrhythmias will be evaluated. Implementation of this model will significantly enhance existing methodological approaches in the Laboratory of Experimental Cardiology.