Figure 5.

3D rendering, filament modeling and quantification of blood vessels in the ischemic brain. (a) Horizontal sections across the cleared ischemic brain at −6.24 mm and −4.26 mm bregma. Between these levels, image stacks at 6.4 × magnification were acquired in the ipsilesional and contralesional striatum (i.e. the core of the middle cerebral artery territory) for a detailed quantitative analysis of microvessels. Within these image stacks the position of the ROIs (508 × 508 µm, labeled with white squares) were selected from the overview image at −6.24 mm bregma by drawing a guide line orthogonal to the midline that passed through the center of the connection of the left and right lateral ventricles with the third ventricle. The ROIs were placed in the most lateral striatum, where it faces the external capsule. (b) 3D vessel rendering and filament tracer model of blood vessels taken from the 508 × 508 × 1500 µm ROI in ipsilateral ischemic and contralateral non-ischemic brain tissue. Reconstructions show a transverse view looking down through a 250 µm slice of the rendered vessels and filament model (contrast stretched with a γ of 3.0). Effect of focal cerebral ischemia on (c) total vasculature length density, and (d) the vasculature length density stratified by vascular diameter. Note that focal cerebral ischemia most markedly affects capillaries with a diameter ≤ 10 µm. Vessels with diameter > 20 µm remain unaffected. Scale bar in (b), 100 µm. Plots in (c) and (d) show mean ± SD values. ***p < 0.001, **p < 0.01, *p < 0.05 compared with corresponding non-ischemic tissue.