Figure 6.

Correlative light Electron Microscopy (CLEM) of the PVS. Panel A: CLEM image of a small artery obtained after merging fluorescent (green tracer, blue nuclei) and EM images of two consecutive slices of the same brain. Red blood cells (RBC) are present in the lumen. Endothelial cells (EC) and smooth muscle cells (SMC) were identified based on location and morphology. The tracer was found in the extracellular space immediately surrounding the smooth muscle layer of the artery and in between the latter and the pericyte (P). Panels B and C are higher magnifications of the vessel wall, without the fluorescent (B) and with the fluorescent (C) signal superimposed. The basement membrane between the EC and the SMC did not present signal. Panel D shows a capillary with tracer immediately below the endothelium. Panel A: scale bar 5 µm Panels B, C: scale bar 1 µm; Panel D: scale bar 5 µm.