“Zebrafishing” for Novel Genes Relevant to the Glomerular Filtration Barrier

Figure 3

Functional assay for glomerular filter integrity measuring systemic fluorescence over the retinal vessel plexus (FITC-eye-assay). 70 kD FITC-labelled dextran is injected in the cardinal vein of anaesthetized morpholino and control-injected fish at 48 hours after fertilization (a). FITC-dextran level in the circulation is measured 24 hours after cardinal vein injection using ImageJ software as baseline value (b) and is additionally measured 48 hours after injection. If leakage of the 70 kD protein occurs at the filtration barrier, it is detectable by the significant loss of fluorescent dextran measured over time (b′), whereas in fish without leakage the protein is not lost and the measured fluorescence remains constant.