[Action potentials of the heart atria and ventricles of Rana temporaria frogs and Cyprinus carpio carp].

Using microelectrode technique, studies have been made on electrophysiological indices (amplitude of AP, amplitude of the plateau, latent period of AP, duration of maximal depolarization, duration of repolarization at different levels) of cells of isolated atrium and ventricles of the carp during both the spontaneous activity and electrical stimulation. The obtained amplitude-temporal parameters were compared to those of the heart in the frog R. temporaria. It was found that the amplitude of AP, the amplitude of the plateau and the duration of the latent period of AP in both the atrium and ventricles of the carp significantly (p less than 0.01) differ from the corresponding indices of the frog. On the contrary, the duration of maximal depolarization and repolarization in cells from homologous parts of the heart is very close in the species investigated.