Figure 7.

Effect of caspase-6 or caspase-8 inhibition on the number of proliferating cells after MCAO. Intravenous administration of a caspase-6 or caspase-8 inhibitor increased the percentage of Ki-67 positive cells after MCAO. (a–l) Fluorescence micrographs of peri-infarct area of the injured hemisphere. Columns (left to right) show Ki-67 immunoreactivity (proliferating cells), DAPI labeling, a merge of the two preceding images, and a higher magnification view of the inset white box in the merged images. Control samples showed scarce Ki-67 positive cells (a–d), whereas samples treated with a caspase-6 inhibitor Z-VEID-FMK (e–h) or caspase-8 inhibitor Z-IETD-FMK (i–l) had an increased percentage of Ki-67 positive cells after MCAO. Arrow in d, h, and l show Ki-67 positive proliferating cells in the peri-infarct region of the infarcted hemisphere; (m) quantification of the mean percentage of Ki-67 positive cells (±S.E.M.) following MCAO. Z-VEID-FMK or Z-IETD-FMK significantly increased the percentage of Ki-67 positive cells (*P<0.01) at 7 days after stroke. Scale bar, 50 μm. n=6 each group