Figure 7

Qx28 protects mammalian hair cells from gentamicin- and CDDP-induced ototoxicity. (A–H) P3 cochlear mouse explants were incubated for 48 hours at 37°C with media (A), Qx28 1mM (B), and the ototoxins alone (C and E) or in combination with Qx28 (10 nM–1 mM) (D and F–H). Tissue was immunostained for myosin VI (red). Two hundred micrometer regions from the middle turn were photographed, and the number of intact outer hair cells (OHCs) in each 30 inner hair cells was counted (G and H). Results are expressed as mean ± SEM. Statistical analysis: 1-way ANOVA with correction for Dunnett’s multiple comparisons test. *P < 0.05, **P < 0.01, ***P < 0.001, and ****P < 0.0001 versus the corresponding ototoxin. Number of independent replicates: n = 4 (GM 100 μM, GM+Qx28 10 μM–1 mM, CDDP 8 μM, CDDP+Qx28 100 μM, 1 mM), n = 3 (additional treatments). Scale bar: 20 μm.