Figure 6.

BBB permeability and reactive gliosis must be analyzed separately in the aged brain, particularly after acute O₃ exposure. A, Representative Merge image of FSCN penetration in the aged cortex, where DAPI indicates nuclear staining. B, Representative Merge image of FSCN penetration in the aged cortex after acute O₃ exposure. C, Representative Merge image of aged cortex labeling microglia (Iba-1), FSCN, and astrocytes (GFAP). D, After acute O₃ exposure. Delineating the specific astrocyte and microglia contribution to BBB integrity was difficult, particularly after acute O₃ exposure. Thus, separate quantitative analyses of FSCN dye penetration and microglia fluorescence was performed. All images were taken with a ×20 objective on a Zeiss LSM800 Airyscan.