Fig. 1.

HH induces the disruption of the BBB, triggering brain edema. C57BL/6 mice were exposed to HH (7600 m altitude) for 24 h. A Brain water content was measured by the wet and dry weight method. B to E HH-treated mice were tail-injected with EB, which circulated for 1 h. This was followed by saline perfusion to remove the dye from circulation. The whole brain was observed for EB infiltration into blood vessels and tissues (B). The residual amount of EB in tissues was measured by colorimetric assay (C). The brain slices were labelled with Laminin by immunofluorescence, and EB distribution in the extravascular tissue was observed (D). The fluorescence intensity of Evans blue was calculated (E). F and G HH-treated mice were tail-injected with 40 kD FITC-dextran for 15 min and subsequently perfused with saline to remove it from circulation. Brain slices were labelled with DAPI, and dextran distribution in the cortex was observed (F). The fluorescence intensity of dextran was measured (G) (*P < 0.05, **P < 0.01 and ***P < 0.001, n = 10)