Figure 5
Auditory brainstem response (ABR) thresholds of better-hearing ears of transgenic mice. (A) ABR thresholds of Tg[PTmc1::Tmc2]; Tmc1∆/∆ (mean ± SD, black line), Tmc1∆/∆ (black dotted line) and wild-type (Tmc1+/+, black dashed line) at P16. The thresholds of Tg[PTmc1::Tmc2]; Tmc1∆/∆ mice were approximately 80 dB SPL, which was significantly better than those of Tmc1∆/∆ mice measured in response stimuli ranging from 8.0 kHz to 22.4 kHz (one-way ANOVA, P < 0.001). The thresholds of Tg[PTmc1::Tmc2]; Tmc1∆/∆ mice were significantly higher than those of wild-type mice (one-way ANOVA, P < 0.001). (B) ABR thresholds of Tg[PTmc1::Tmc2]; Tmc1∆/∆ mice at P16, P19, P22 and P25. The thresholds elevated with age until there were no detectable responses to 90 dB SPL stimuli at P25. (C) ABR thresholds of Tg[PTmc1::Tmc2]; Tmc1+/+ and wild-type mice at P16 and P30. Their mean ABR thresholds were not significantly different from those of wild-type mice at P16 and P30 (Student’s t-test, P > 0.05). (D) ABR thresholds of Tg[PTmc1::Tmc1]; Tmc1∆/∆ and wild-type mice at P16 and P30. The thresholds of Tg[PTmc1::Tmc1]; Tmc1∆/∆ mice were not significantly different from those of wild-type mice at P16 and P30 (Student’s t-test, P > 0.05). (E) ABR thresholds of Tg[Tmc1∆Ex8_9]; Tmc1∆/∆ and Tmc1∆/∆ mice at P16. Responses could not be detected to 90 dB SPL stimuli at any frequencies in Tg[Tmc1∆Ex8_9]; Tmc1∆/∆ mice or Tmc1∆/∆ mice.
