PAI-1 inhibition in zebrafish leads to vascular leakage.

(A) Zebrafish embryos three-days post-fertilization (3dpf) were incubated with PAI-039 inhibitor (50 μM) or solvent (DMSO 1%) for 6 hours. Vascular leakage was visualized by injecting 2000 kDa tetramethylrhodamine(TMR)-dextran into the duct of cuvier. Intersegmental vessels are depicted in green, vascular lumen and leakage from vessels in red (scale bar 100 μm). (B) Quantification of extracellular fluorescence data from at least 15 fish were analysed for PAI-039 or solvent treatments respectively (mean + SEM, * p < 0.05). (C) 3dpf zebrafish were injected with 70 kDa TMR-dextran and incubated with PAI-039 inhibitor (25 μM) or solvent (DMSO 1%) for 3–4 hours. Vascular leakage occurs in the hindbrain of zebrafish (arrow heads) (scale bar 100 μm). (D) Quantification of extracellular fluorescence data from at least 23 fish were analysed for PAI-039 or solvent treatments respectively (mean + SEM, ** p < 0.01).