Expression and localization of LRP in the damaged cortex of the mouse brain after MCA occlusion. (A) Representative immunoblots against LRP and β-actin as an internal control are shown. The expression of LRP is up-regulated in the ipsilateral hemisphere at 6 and 24 hours after MCA occlusion, whereas it is not changed in the contralateral hemisphere. (B) Quantitative data are shown as fold increase. Data are mean ± SD of 6 experiments. *P < .05; **P < .01. ipsi indicates ipsilateral hemisphere; contra, contralateral hemisphere. The time after MCA-O is indicated in hours. Localization of LRP in the normal area (C-E) or the damaged border area (F-H) at 24 hours after MCA-O is shown by immunofluorescence microscopy. In the normal area, LRP immunoreactivity (red: rodamine) localized at neuron-like cells (arrowheads in panel C) but not at CD31 (green: fluorescein) positive endothelial cells (arrows in panels D-E). At the damaged border area, it localized at both globular cells (arrowhead in panel F) and CD31-positive endothelial cells (arrow in panels G-H). The scale bar represents 50 μm.