Figure 10.

Flubendazole induces increased number of cells in M-phase. A. 5 dpf fish were either treated with 400 µM neomycin or mock-treated in vehicle for 1 hr, and then exposed to flubendazole for 48 hrs. Fish were immunostained with an antibody to phospho-Histone H3 to assess the number of cells in M-phase at the time of death. Increased numbers of PH3+ cells are present in flubendazole-treated fish, regardless of whether native hair cells were killed by neomycin or not (p's < 0.001) and more labeled cells were seen in neuromasts after neomycin treatment than controls after flubendazole exposure. B. Flubendazole reduces hair cell regeneration primarily between 14–28 hrs post-damage. Fish were treated with 400 µM neomycin for 1 hr, and then treated with DMSO vehicle or 5 µM flubendazole for one of three time periods (0–14 hrs, 14–28 hrs or 28–44 hrs post-neomycin). Larvae were then held in EM only for the remainder of time prior to fixation at 48 hrs and immunostained for GFP+ hair cells. There is a marked decrease in the number of hair cells when proliferating cells are suspended in M-phase specifically during the 14–28 hr incubation period after neomycin treatment, but not during other periods. For each fish, 7 neuromasts were examined (n = 10 fish/group). Error bars indicate +/− 1 SD.