Willott J F, Turner J G, Sundin V S
Department of Psychology, Northern Illinois University, DeKalb, IL, USA.
Hear Res. 2000 Apr;142(1-2):79-88. doi: 10.1016/s0378-5955(00)00014-9.
The effects of exposure to an augmented acoustic environment (AAE) on auditory function were evaluated in mouse strains that exhibit various degrees and time courses of progressive hearing loss (BXD-22, BXD-12, BXD-16, BXD-14, BALB/cJ), and in normal-hearing CBA/CaJ mice. Beginning at age 25 days, mice were exposed 12 h every night to a 70 dB SPL broadband noise AAE. The AAE was maintained for at least 30 days in each strain. Same-strain control mice were age-matched and maintained under normal vivarium acoustic conditions. The auditory brainstem response (ABR), acoustic startle response amplitude, and prepulse inhibition (PPI) were used to assess the auditory system. Exposure to the AAE resulted in improved auditory performance (better PPI, lower ABR thresholds) when hearing impairment was present, but not when hearing was normal. The ameliorative effects occurred irrespective of a mouse's age at the onset of hearing loss, as long as initiation of AAE treatment preceded the occurrence of severe hearing loss. If AAE treatment was delayed beyond such a point, loss of threshold sensitivity progressed as usual, although PPI could still benefit. Finally, AAE treatment can slow, but not prevent, the occurrence of severe genetically determined hearing loss.
在表现出不同程度和时间进程的进行性听力损失的小鼠品系（BXD - 22、BXD - 12、BXD - 16、BXD - 14、BALB/cJ）以及听力正常的CBA/CaJ小鼠中，评估了暴露于增强声学环境（AAE）对听觉功能的影响。从25日龄开始，小鼠每晚暴露于70 dB SPL的宽带噪声AAE中12小时。每个品系中AAE持续至少30天。同品系对照小鼠年龄匹配，并在正常饲养箱声学条件下饲养。使用听觉脑干反应（ABR）、听觉惊吓反应幅度和前脉冲抑制（PPI）来评估听觉系统。当存在听力障碍时，暴露于AAE会导致听觉性能改善（更好的PPI，更低的ABR阈值），但听力正常时则不会。只要AAE治疗在严重听力损失发生之前开始，改善效果就会出现，而与小鼠听力损失开始时的年龄无关。如果AAE治疗延迟超过这一点，阈值敏感性的丧失会照常进展，尽管PPI仍可能受益。最后，AAE治疗可以减缓，但不能预防严重的遗传性听力损失的发生。
