Fig. 1

a Immunofluorescence labeling of the tight junction (TJ) TJ marker occludin and the vascular basement membrane marker collagen IV reveals detectable occludin-positive TJ strands in vessels showing FITC-albumin (FITC) extravasations in ischemia-affected striatal areas. FITC-albumin extravasations indicative of BBB breakdown become visible as early as 2 h after pMCAO, while 1 h and 30 min pMCAO animals did not reveal FITC-albumin extravasations. Differences in the expression pattern of occludin between striatal and cortical regions were not observed. Nuclei are visualized with DAPI. Inset: contralateral control area; Scale bar: 10 μm. b Protein levels of occludin were analyzed in striatal and cortical areas using Western Blot analysis. Reduced occludin protein levels were found in the ischemia-affected striatum (p = 0.029; n = 6; Student’s t-test), whereas the difference in cortical areas failed to reach statistical significance (cortex: p = 0.167). Data are given as means. Error bars indicate SD