Time course of cell proliferation after global ischemia and effect of ischemia duration on proliferation in the SGZ. In both sets of experiments, BrdU was administered 24 hr before the animal was killed. A, The number of BrdU immunoreactive nuclei in the SGZ of animals killed 6 d (n = 12), 9 d (n = 8), 11 d (n = 7), 2 weeks (n = 6), 3 weeks (n = 7), 4 weeks (n = 8), or 5 weeks (n = 6) after 10 min of global ischemia (•). Control animals (n = 10) were untreated (○). B, BrdU-positive nuclei in the SGZ of animals killed 8 d after 2 (n = 8), 3 (n = 6), 4 (n = 6), 5 (n = 6), or 10 (n = 8) min of ischemia. Data are mean ± SEM. Error bars are omitted where they extend beyond the symbols. *p < 0.05 compared with control.