Fig. 6

Damage to the brain parenchyma characterised by vasogenic oedema in animal models. a HE staining showing filling of the SSS with the expanded rubber implant. Microscopic image showing erythrocyte scattering and interstitial enlargement around the oedemic area, with increases in capillary-like structures (black arrows). b Nissl staining showing an obvious decrease in the number of normal neurons and abnormal arrangement of cells. c Immunohistochemical sections showing increased expression of EPO and VEGF-A and decreased expression of claudin-5 and ZO-1 around the oedemic area. d TEM results showing the vascular lumen and endothelial cells under low power (× 15,000) and TJs located between endothelial cells under higher power (×50,000). The intact TJ appears as a black-dense band in the sham group (red arrow). This band is almost disappeared in the model group (red arrow), which exhibited interstitial enlargement around the vascular lumen. e Quantification of immunohistochemical analysis. f Quantification of claudin-5 and ZO-1 in the serum. Scar bars = 100 μm in (a–c), Scar bars = 2 μm on the lower power lens maps and 500 nm on the higher power lens maps in d. Values are expressed as mean standard deviation. *P < 0.05, **P < 0.01, ***P < 0.001. SSS: superior sagittal sinus; EPO: erythropoietin; VEGF-A: vascular endothelial growth factor A; ZO-1: zonula occludens 1; TEM: transmission electron microscopy; TJ: tight junction