The potassium channel blocker, dalfampridine diminishes ouabain-induced arrhythmia in isolated rat atria.

The aim of the present experiment was to investigate the possible antiarrhythmic effects of dalfampridine in ouabain-induced arrhythmia in rats. Twenty-four male rats including the control and dalfampridine-incubated (100 µM to 10 mM) ouabain-stimulated (40 µM) groups were used. After induction of anesthesia, the atria were isolated and the time of onset of arrhythmia and asystole were recorded. The contractile force of atria was also measured. Dalfampridine at concentration of 1 mM significantly postponed the onset of arrhythmia and asystole compared to control group (p ≤ .05). Ouabain significantly increased the atrial beating rate in control group (p ≤ .05), while pretreatment of isolated atria with dalfampridine reversed this effect. Incubation of isolated atria with ouabain did not alter the contractile force in both control- and dalfampridine-treated groups (p > .05). It is concluded that dalfampridine might possess antiarrhythmic properties in reducing the atrial arrhythmias.