Heart rate twenty minutes after ischemia-reperfusion. After 20 mins of reperfusion, heart rate (HR) was significantly lower in animals exposed to O3 when compared to FA. There were no other significant differences in post-ischemia HR between any groups or at any other time point. Values are means ± SEM (n = 5-8 in each group). *Significantly different from FA; p < 0.05.