Efferent-mediated protection from acoustic overexposure: relation to slow effects of olivocochlear stimulation.
Efferent-mediated protection from acoustic overexposure: relation to slow effects of olivocochlear stimulation.
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传出介导的声音过度暴露保护：与橄榄耳蜗刺激的缓慢影响有关。
DOI：
10.1152/jn.1995.73.2.506
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发表时间：
1995
期刊：
影响因子：
--
通讯作者：
Liberman,MC
中科院分区：
文献类型：
--
作者：
Reiter,ER;Liberman,MC
1.本研究试图解决橄榄耳蜗（OC）传出激活在保护内耳免受声过度刺激中的作用的报道中的差异：在以前的研究中，激活豚鼠OC系统减少了10 kHz音调单耳暴露1分钟引起的阈值偏移;而猫单侧OC激活对双耳暴露于10分钟6-kHz音调后的阈值偏移没有影响。2.在这项研究中，麻醉和箭毒豚鼠单耳或双耳暴露于不同持续时间（1-5分钟），频率（6 - 10 kHz）和强度（105-118 dB SPL）的音调。对于每种暴露条件，比较了具有不同OC激活水平的耳朵之间的阈值偏移：在某些情况下，OC束（OCB）在声学过度暴露期间（和/或之前）进行电刺激;在其他情况下，OCB在暴露前被切断;在对照情况下，OCB既不被切断也不被电刺激。3.电刺激的OCB提供的同时，声学过度刺激产生显着减少的阈值偏移，只有在较高的频率（8和10 kHz）和较短的持续时间（1和2分钟）的声学曝光。1分钟暴露的保护作用可以通过OCB的预先刺激而消除，即，如果在声过度刺激前4 min开启OC刺激。（250字处删节）
1. The present study attempts to resolve discrepancies in the reported role of olivocochlear (OC) efferent activation in protecting the inner ear from acoustic overstimulation: in previous studies, activating the OC system in guinea pigs reduced the threshold shift caused by 1 min monaural exposure to a 10-kHz tone; whereas unilateral OC activation in cats had no effect on threshold shifts following binaural exposure to a 10 min 6-kHz tone. 2. In this study, anesthetized and curarized guinea pigs were exposed either monaurally or binaurally to tones of different duration (1-5 min), frequency (6 to 10 kHz) and intensity (105-118 dB SPL). For each exposure condition, threshold shifts were compared among ears with different levels of OC activation: in some cases, the OC bundle (OCB) was electrically stimulated during (and/or before) the acoustic overexposure; in others, the OCB was cut before the exposure; in control cases, the OCB was neither cut nor electrically stimulated. 3. Electrical stimulation of the OCB delivered simultaneously with acoustic overstimulation produced significant reductions in threshold shift only for acoustic exposures at higher frequencies (8 and 10 kHz) and shorter durations (1 and 2 min). The protective effects on 1-min exposures could be extinguished by prior stimulation of the OCB, i.e., if the OC stimulation was turned on 4 min before the acoustic overexposure.(ABSTRACT TRUNCATED AT 250 WORDS)