Figure 4.

Few P-glycoprotein/caveolin1 complexes occur in rat brain microvessels. (a) Brightfield image of a cross section of a rat brain microvessel stained with H & E showing the endothelial cells (E) surrounding the vessel lumen (L) and pericytes (P) surrounding the endothelial cells. A red blood cell (RBC) sits in the lumen. (b) Representative immunofluorescence images of dual stains for P-glycoprotein (PgP) (green) or PTRF (green) and caveolin1 (CAV1) (red) in cross-sections of rat brain microvessels. The negative control shows fluorescence in the absence of primary antibody. DAPI (blue) counterstain indicates nuclei. (c) Representative proximity ligation assay results for PgP/ CAV1 binding and PTRF/ CAV1 binding (green signals) in cross sections of rat brain microvessels. Blue staining indicates nuclei. The negative control image shows the background reaction of the PLA reagents in the absence of antibodies. The bar represents 20 µm. Images were acquired from at least three pools of three rats.