Original paper :AATEX 6(1):72-78,1999
Abstract
We have studied the pharmacological and toxicological effects of cardiovascular drugs on chick embryos using electrocardiograms in order to develop alternatives to the use of mammals. Recently, proarrhythmic actions induced by antiarrhythmic drugs have been widely studied. In this study, we investigated the pharmacological effects of antiarrhythmic drugs, Ia(procainamide), Ib(lidocaine), Ic(flecainide), II(propranolol) and IV(verapamil)types, as classified by Vaughan Williams. When a single injection of drugs was performed into the air sac of fertile eggs of White Leghorns on the 16th day of incubation, all drugs decreased HR in a dose-dependent manner. Also, when higher dosages of drugs were injected, these drugs induced various kinds of arrhythmias, i.e., S-A or A-V blocks, as shown in mammals. The intervals of PQ, QRS and QT waves varied depending on the drugs used. However, the ECG waves exhibited the same changes seen in mammals with a few exceptions. Our ECG recording system using chick embryos may be applicable for screening tests for proarrhythmic actions of antiarrhythmic drugs.
Key words: Chick embryo, alternative animal, antiarrhythmic drug, electrocardiogram, proarrhythmic action