Involvement of Inflammatory Cytokines in Antiarrhythmic Effects of Clofibrate in Ouabain-Induced Arrhythmia in Isolated Rat Atria

Figure 4

A general comparison in chronotropic and inotropic features between vehicle- and clofibrate-treated groups. Complete records of isolated atrial beats of vehicle-treated (a) and clofibrate-treated (b) groups. In vehicle-treated group (a), ouabain-induced arrhythmia is obvious and asystole happens after arrhythmia. The severity of arrhythmia in clofibrate-treated group is lesser and, in some samples (b), no asystole was seen until several hours. Atrial beatings before incubation of ouabain in vehicle-treated (c) and clofibrate-treated (d) groups. As shown, atrial beatings and contractile force are similar in both groups. Ouabain-induced arrhythmia in vehicle-treated (e) and clofibrate-treated (f) groups. The shape of arrhythmia in vehicle-treated group is bigeminy (twin spikes with strong force), which is the typical manifestation of ouabain-induced arrhythmia (a). In clofibrate-treated group (b), spikes of arrhythmia are weak and irregular, and it happens much later than vehicle-treated group. Ouabain-induced asystole in vehicle-treated (g) and clofibrate-treated (h) groups. Time of onset of asystole in clofibrate-treated group (h) is later than vehicle-treated group.

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