Time-course of plasma TNF-α levels following various reperfusion times, after the onset of 90 min of ischemia. "Control" indicates mice that underwent no surgical procedure. "Sham" indicates mice that underwent surgical procedure with no vascular occlusion followed by reperfusion, while "I/R" indicates mice that underwent surgical procedure with vascular occlusion for 90 min followed by reperfusion for various lengths of time. Values are expressed as mean ± SEM. *P < 0.05 female group vs. male group (n = 5–9 mice per each time point/group). A: I/R group; B: Sham group.