Figure 3.

The glucocorticoids dexamethasone and prednisolone enhance hair cell regeneration. A, Fluorescent confocal images of GFP+ hair cells treated continuously for 48 h with DMSO vehicle (left), 5 μm dexamethasone (middle) or 5 μm prednisolone (right), after 400 μm neomycin treatment for 1 h. Scale bar, 2.5 μm. B, C, An increase in total number of hair cells occurs following exposure to either dexamethasone (B) or prednisolone (C). Graphs indicate the mean total number of GFP+ hair cells among seven neuromasts from 10 fish after neomycin damage (triangles) or mock treatment (squares) and subsequent 48 h exposure to dexamethasone or prednisolone (open symbols and dotted lines) compared with DMSO vehicle-only (filled symbols and solid lines). Analysis by two-way ANOVA showed significant main effects of drug, concentration and an interaction for dexamethasone and prednisolone compared with DMSO control fish in both neomycin and mock-treated groups. Error bars indicate ±1 SD.