Fig. 13

Metalloproteases in the brain of blast-exposed rats. Enriched brain vascular fractions were prepared from control and blast-exposed rats at 6 weeks post-exposure. Protein extracts (20 µg) from the enriched vascular fractions were analyzed by gelatin zymography. Panel a shows vascular upregulation of gelatinase activity associated with MMP-2, MMP-9 and their precursor proteins in the blast-exposed animal (B) as compared to control (C). Panels b, c show a brain arterial cross-section from a blast-exposed rat stained with antibodies against α-SMA (b, green) and MMP-9 (c, red). Panel d shows MMP-9 expression (green) in brain arterial smooth muscle of a blast-exposed rat at 13 months post-exposure. Panel e showns the same vessel in d stained with collagen IV (red). Brain sections of blast-exposed animals were stained with anti-rat IgG (red) and counterstained with DAPI (blue) f, g. Leakage of IgG could be seen in perivascular areas within the corpus callosum f or the entorhinal cortex g. Scale bars, 20 µm b, c 10 µm d, e 100 µm f; 300 µm g