Figure 7.

Activation of caspase-3 after permanent focal cerebral ischemia. Immunostaining for activated caspase-3 (Cas-3) cells shows that Cas-3 was expressed throughout the infarct at 24 h in cells with a microglial morphology (inset) in both TNF-KO and C57BL/6 mice. Immunofluorescence photomicrographs of the peri-infarct area in a C57BL/6 mouse shows colocalization between Cas-3 (red) and CD11b⁺ cells 24 h after pMCAo. All Cas-3⁺ cells colocalized with CD11b, with the combined green and red fluorescence shown as yellow (arrow). Immunofluorescence photomicrographs of the infarct in a C57BL/6 mouse stained for Cas-3 (red, arrow) and NeuN (green) 24 h after MCA occlusion are shown. Cas-3 is not expressed by neurons, because red fluorescence and green fluorescence do not coincide. Scale bars: 20 μm; insert, 10 μm.