Figure 3.

Reduction in endothelial fenestrations (arrowheads) after inhibition of VEGF signalling. (A and B) Transmission electron microscopic images of islet capillaries showing thin endothelium and abundant fenestrations with diaphragms under baseline conditions compared to thick endothelium, few fenestrations, and abundant caveolae after AG-013736 for 21 days (Kamba et al, 2006). (C and D) Transmission EM images of renal glomerular capillaries comparing thin endothelium and abundant fenestrations under baseline conditions with thick endothelium and few fenestrations after Ad-sVEGFR-1 for 14 days (Kamba et al, 2006). (E and F) Scanning electron microscopic images of luminal surface of glomerular capillaries showing abundant endothelial fenestrations under baseline conditions and few fenestrations after Ad-sVEGFR-1 for 14 days (Kamba et al, 2006). (G) Bar graph showing significantly higher concentration of TSH in serum as a measure of altered thyroid function after AG-013736 for 21 days. (H) Bar graph showing increasing amount of proteinuria, indicated by proportion of mice with Albustix values of ++ or greater (⩾100 mg albumin/dl of urine), with increasing dose of AG-013736 for 7 days. (I) Diagram of hypothetical shuttling of diaphragms between endothelial fenestrations and caveolae, with VEGF inhibition driving the process to the right and VEGF signalling driving it to the left (Kamba et al, 2006). Scale bars: 0.3 μm in (A) and (B); 1 μm in (C) and (D); 0.5 μm in (E) and (F).