BrdU labeling
BrdU (Sigma), the thymidine analog that is incorporated into the DNA of dividing cells during S-phase, was used for mitotic labeling. BrdU (50 mg/kg) was intraperitoneally injected daily for thirteen consecutive days into ischemic rats starting 1 day after MCAO. To quantify BrdU immunoreactive cells, BrdU positive cells co-localizing with or without CM-DiI dye were counted in the infarcted area from each rat. Data was presented as average of BrdU immunoreactive cells in ipsilateral hemisphere from five rats.