Fig. 2

Dextran is released into bloodstream after gavage in adult zebrafish (Danio rerio). In this assay, fish were gavaged with a 2% RITC-Dextran solution with a molecular weight of 10,000 Da (n = 15). Representative images demonstrate an increase in fluorescence intensity within the vascular lumen (black arrows) of the caudal fin in the positive control group (RITC-dex + ethanol; D–F) compared with the test group (RITC-dex; G–I) at 2 h postgavage. Vehicle: Negative control. A, D, and G: Images were acquired using a fluorescent filter with excitation/emission wavelengths of 559–585 nm/600–690 nm. B, E, and H: Images were captured in the conventional channel. C, F, and I: composite images merging the two channels. All images were acquired using consistent magnification and exposure settings. Scale bar represents 100 µm. RITC, rhodamine B isothiocyanate.