Effect of flavone in a canine model of myocardial stunning.

Putative cardioprotective action of flavone (10, 20 and 30 mg/kg) was investigated in a canine model of regional ischemia (20 min) followed by 60 min of reperfusion. In animals pretreated with vehicle, myocardial stunning was evidenced by significant changes in hemodynamic parameters (depressed mean arterial pressure, LV peak (+) dP/dt, LV peak (-) dP/dt and elevated LV end-diastolic pressure) and biochemical parameters (decreased myocardial ATP and rise in plasma malondialdehyde or MDA; a marker of free radical-induced injury). A reduction in plasma MDA was noted with 20 and 30 mg/kg flavone, although attenuation of myocardial dysfunction was evident with all the three doses. The results suggest that besides a significant dose-dependent antioxidant effect, flavone may also have some cardioprotective actions per se, which needs to be further investigated.