Figure 2

Representative immunohistochemistry analysis of High-mobility group box 1 (HMGB1) in the brain cortex. (A) HMGB1 expression in the sham group: HMGB1 could be observed in the nucleus in the sham group, cells were seldomly stained positive for cytosolic HMGB1. (B, C) HMGB1 staining in the 2-h and day-1 groups post subarachnoid hemorrhage (SAH), respectively. The quantity of cells positive for cytosolic HMGB1 obviously increased in the SAH groups at 2 h and day 1 after SAH. (D) Black boxes show the view of observation. (E, F and G) Enlarged images of A, B and C, respectively. Positive cells were defined as presenting buffy grains in cytoplasm as shown by arrows. Scalar bars present 20 μm. (H) Quantification of density of cells positive for cytosolic HMGB1. Values were obtained from averaging three sections per animal. SAH induced translocation of HMGB1 in the cortex near the subarachnoid space as early as 2 h post SAH. Bars represent the mean ± standard error (n = 6); ^# P < 0.01 compared with the sham group.