Lauer Amanda M
Department of Otolaryngology-HNS, Center for Hearing and Balance, Johns Hopkins University School of MedicineBaltimore, MD, United States.
Front Neurosci. 2017 Jun 2;11:304. doi: 10.3389/fnins.2017.00304. eCollection 2017.
Studies have suggested a role of weakened medial olivocochlear (OC) efferent feedback in accelerated hearing loss and increased susceptibility to noise. The present study investigated the progression of hearing loss with age and exposure to a noisy environment in medial OC-deficient mice. Alpha9 nicotinic acetylcholine receptor knockout (α9KO) and wild types were screened for hearing loss using auditory brainstem responses. α9KO mice housed in a quiet environment did not show increased hearing loss compared to wild types in young adulthood and middle age. Challenging the medial OC system by housing in a noisy environment did not increase hearing loss in α9KO mice compared to wild types. ABR wave 1 amplitudes also did not show differences between α9KO mice and wild types. These data suggest that deficient medial OC feedback does not result in early onset of hearing loss.
研究表明，内侧橄榄耳蜗（OC）传出反馈减弱在加速听力损失和增加对噪声易感性方面起作用。本研究调查了内侧OC缺陷小鼠的听力损失随年龄增长以及暴露于噪声环境下的进展情况。使用听觉脑干反应对内耳9型烟碱型乙酰胆碱受体敲除（α9KO）小鼠和野生型小鼠进行听力损失筛查。在安静环境中饲养的α9KO小鼠在成年早期和中年期与野生型小鼠相比，未表现出听力损失增加。与野生型小鼠相比，将α9KO小鼠置于噪声环境中对内耳OC系统造成挑战，并未增加其听力损失。ABR波1的振幅在α9KO小鼠和野生型小鼠之间也未显示出差异。这些数据表明，内侧OC反馈缺陷不会导致听力损失的早期发生。
