Effects of denudatine on action potential of ventricular fibers and its inhibition on arrhythmogenic action of aconitine

The effects of denudatine and aconitine on the action potential of isolated ventricular fibers were studied in 20 porcine hearts and the inhibitory action of denudatine on arrhythmogenic action of aconitine was observed. Denudatine (30 mg/1) depressed the amplitude and the maximal rate of rise of the action potential, reduced the action potential duration and the effective refractory period, but did not inhibit the arrhythmogenic action of aconitine. Denudatine (150 mg/l) depressed the amplitude of action potential so much that it tended to change the action potential into a slow responsive type and inhibited completely the arrhythmogenic action of aconitine. It seems that denudatine possesses an inhibitory effect on Na+ influx in ventricular fibers.