Fig 4.

Delayed PFT-α treatment increased the survival and migration of newly generated NPCs in the lesioned cortex. (A) Rats were subjected to MCAo on day 0. Newly generated cells were pre-labeled with BrdU on day 5 after stroke. PFT-α or vehicle was given 1 day after the BrdU labeling. Density of BrdU immunoreactivity in (B) SVZ or (C) cortex on days 10 and 21 after MCAo was normalized to the level of BrdU activity in vehicle group on Day 10. (B) In the SVZ, BrdU-labeled cells were mainly present on day 10 after MCAo. Few BrdU cells were found on day 21. PFT-α treatment significantly increased the density of BrdU cells on day 10 in SVZ. (C) In the lesioned cortex, fewer BrdU cells were found on day 10. Significantly increased BrdU labeling was found on day 21. PFT-α treatment enhanced BrdU labeling in the lesioned cortex both on days 10 and 21 after MCAo. (D) Correlation of the functional outcomes with migration of NPCs to the lesioned cortex in stroke rats. The behavioral improvement in horizontal activity (HACTV) on days 14 and 21 was calculated using the following equation. % improvement = (HACTV on day 14 or 21 – HACTV on day 2)/(HACTV on day 2) *100%]. BrdU (+) cells in the lesioned side cortex was examined on day 21 after MCAo. There is liner correlation between the number of BrdU cells in cortex and HACTV improvement at 14 days (r=0.828, p=0.002, black tracing) and 21 days (r=0.644, p=0.032, red tracing) after MCAo. (E) Photomicrographs indicate that PFT-α treatment increased BrdU-labeled cells in the lesioned cortex on day 21 after MCAo. Calibration= 50 μm.