Hair cell regeneration is blocked by inhibition of mitosis.

<p>ET4:GFP larvae were treated at 5 dpf with neomycin or copper for 1 h and incubated in flubendazole for 48 h. (A) Those not treated with flubendazole continued to add mature hair cells. Two-way ANOVA found significantly more cells expressed GFP than parvalbumin (<i>p</i><0.001), indicating the presence of hair cell precursors. Bonferroni post-hoc analysis confirmed a significant difference in control and ototoxin-treated groups between GFP- and parvalbumin-positive hair cell counts at 48 hpt (**, <i>p</i><0.01; ***, <i>p</i><0.001). (B) Those treated with flubendazole exhibited little or no increase in mature hair cells. There were at most 1 or 2 parvalbumin-negative precursors present per neuromast, indicating that undifferentiated precursors did not accumulate. <i>N</i> = 8 fish per group. Error bars are +/− SD.