The ratio of larvae at the starting point curve (A), the area under the curve (AUC) of the ratio of larvae at the starting point curve (B), and the percentage of larvae that finished swimming (C) according to the contrast-optomotor response assay after 24 h exposure at 4 dpf to 0 (control), 5, 10, and 15 μM gentamicin. An asterisk (∗) indicates a p-value < 0.05 as compared with the Gentamicin 15 μM group, a dagger (†) indicates a p-value < 0.05 as compared with the Gentamicin 10 μM group, and a double dagger (‡) indicates a p-value < 0.05 as compared with the Gentamicin 5 μM group by one-way ANOVA with post-hoc Tukey HSD test.

Graded-color class on a logarithmic scale in 16 steps to make a contrast-optomotor response assay.

The ratio of larvae at the starting point curve (A), the area under the curve (AUC) of the ratio of larvae at the starting point curve (B), and the percentage of larvae that finished swimming (C) according to the contrast-optomotor response assay after 24 h exposure at 4 dpf to 0 (control), 5, 10, 15 μM digoxin. Asterisk (∗) indicates a P value < 0.05 compared with the Digoxin 15 μM group, dagger (†) indicates a P value < 0.05 compared with the Digoxin 10 μM group, and double dagger (‡) indicates a P value < 0.05 compared with the Digoxin 5 μM group by the one-way ANOVA with post-hoc Tukey HSD test.

Illustration of the swimming tray with six swimming lanes for zebrafish larvae (A) and the contrast-optomotor response assay with video recording system (B).

H&E-stained transverse sections and immunohistochemical analysis of Müller glia (green) of zebrafish larvae after 24 h exposure at 4 dpf to 0 (control 1; A and A′), 5 (B and B′), 10 (C and C′), 15 μM gentamicin (D and D′), 0 (control 2; E and E′), 5 (F and F′), 10 (G and G′), or 15 μM digoxin (H and H′).