/To proof whether the treatment of the larvae with NFP instead of MTZ induces a FSGS-like phenotype, we analyzed the glomeruli after the treatment. We found that the fluorescence intensity of mCherry correlated with the expression of podocin (Fig. 2C). Moreover, we identified an activation of parietal epithelial cells (PECs) in different ways. Thus, H&E staining showed a significant increase of the height of PECs (Fig. 2C and 2D). After 48 hours of NFP treatment, mean cellular height was 2.35 μm in Ctrl (n=16) and increased to 7.11 μm in the MTZ-treated (p< 0.0001; n=14) and to 6.12 μm (p< 0.0001; n=15) in the NFP-treated larvae. Additionally, we found by immunofluorescence staining that the activated PECs were strongly Pax2a-positive (Fig. 3A). These cuboidal Pax2a-positive cells were found on the capillary tuft after NFP-induced podocyte depletion. Quantification of Pax2-positive cells showed an approximately 10-fold higher number of cells per μm² in the MTZ group (3.2 × 10⁻³ per μm² (p< 0.0001; n=24)) as well as in NFP group (2.3 × 10⁻³ per μm² (p< 0.0001; n=25)) in contrast to the Ctrl group (3.2 × 10⁻⁴ per μm² (n=25)).