procainamide and ajmaline produced a marked protective effect against aconitine-induced ventricular extrasystole , but were not so effective against aconitine-induced ventricular fibrillation , while oxprenolol and , to a lesser degree , propranolol were effective against the latter type of aconitine arrhythmias .
C0042510
ventricular
C0033497
propranolol