STL- (green) and anti-vWF- (red) staining in treated and non-treated SHRSP. Comparing treated (B, 24 weeks old, cortex, magnification 200) and non-treated (C, 24 weeks old, cortex, magnification 200) animals an increased number of vWF-positive small vessels is detectable in the treated rats (D, histogram, y-axis with mean ratio of vWF-/STL-positive vessels in%). A - vWF threads stick to the inner vessel wall indicating small endothelial injuries (24 weeks old treated SHRSP, basal ganglia, magnification 400). A `- Negative control for vWF (Cy3 donkey x rabbit). DAPI - 4',6-diamidino-2-phenylindole, fluorescent stain for DNA detection.