Figure 4.

Overview and quantification of BrdU-labeled blood vessels in the non-injured and injured adult rat brain. (A) At 3 days after stroke, BrdU was incorporated preferentially into 6.3% of the neurons in the dentate gyrus (DG). BrdU-positive nuclei also co-localized with the marker of rat endothelial cells, RECA, in 17% of blood vessels in the rat cortex in remote areas (RA) relative to the infarct location. By triple immunostaining the newly incorporated cells had a patchy distribution in 14.6% of existing blood vessels. By day 28 after the stroke, BrdU-positive cells were also found in 11.3% of the branched blood vessels in the infarcted area and in 6.4% of the blood vessels in the region of soft tissue beyond the fibrotic scar (B). (C) At day 3 post-stroke, prolyl 4-hydroxylase (P4Hbeta) was expressed in 5.2% of the endothelial cells detaching from the wall of the disintegrating blood vessels. Their number increased to 20.7% by day 14 after cerebral ischemia. By day 28 after stroke, new blood vessels were emerging in the perinfarcted area, 18% of which were BrdU+. More (38%) double labeled BrdU/RECA-positive blood vessels densely were found in the scar region while 7% double labeled BrdU/RECA-positive blood vessels were localized in the region beyond the glial scar, IR. At the same time, a small fraction (3.3%) of double labeled blood vessels were still present in remote areas relative to the stroke.