Figure 3

Microsphere embolism induces microglia activation in brain of experimental animals. (A) Temporal changes in ED1, HMGB1, and CD3 expression in ME rats. (B) Quantification of the normalized protein levels shown in (A). The data are expressed as percentages of values obtained from sham animals (mean ± SEM, n = 6 rats). **P <0.01; ***P <0.001 vs. sham. (C) H&E staining indicated that the presence of microglial nodules was noted ipsilateral to microsphere embolism. No infiltration of leukocytes, monocytes or macrophages was observed. Scale bar = 200 μm. (D) Immunohistochemical localization of ED1 (red)- and Iba1 (green)-positive cells in the microembolic brain. Iba1 labeling was used to identify the microglial population. Double-labeling studies revealed that Iba1 and ED1 staining were present in the same cell populations in areas of ME injury. Scale bar is 50 μm (a-i) and 20 μm (j, k, l). (E) Co-localization between the Ki-67 antigen and ED1-immunoreactive microglial cells in the ipsilateral region of brain. Scale bar = 50 μm. ME, microsphere embolism.