Davis R R, Cheever M L, Krieg E F, Erway L C
Bioacoustics and Occupational Vibration Section, Physical Agents Effects Branch, National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Cincinnati, OH 45226, USA.
Hear Res. 1999 Aug;134(1-2):9-15. doi: 10.1016/s0378-5955(99)00060-x.
The CBA/CaJ (CB) and C57BL/6J (B6) inbred strains of mice were exposed for 1 h to noise intensities between 98 and 119 dB SPL. Previous studies indicated that the B6 mice exhibited permanent threshold shifts (PTS) after 1h exposure to 110 dB, whereas the CB mice did not exhibit any PTS. These differences in susceptibility to noise-induced hearing loss (NIHL) appear to be due to a gene for age-related hearing loss (AHL). The current study was designed to determine dose-response curves for NIHL over the ranges of intensities of noise that would characterize the B6 and CB inbred strains of mice. Because of the considerable differences in sensitivity to NIHL, the noise exposures for the two strains overlapped only at 110 and 113 dB. Nevertheless, the two strains exhibited two different dose-response curves, offset and with different slopes. We postulate that the B6 strain of mice exhibits a more linear increase for PTS from 98-113 dB, consistent with incremental effects on some metabolic physiological mechanism(s); the abrupt transition in NIHL between 113 and 116 dB for the CB mice is consistent with an ototraumatic structural injury.
将CBA/CaJ（CB）和C57BL/6J（B6）近交系小鼠暴露于98至119分贝声压级的噪声强度下1小时。先前的研究表明，B6小鼠在暴露于110分贝的噪声1小时后出现永久性阈移（PTS），而CB小鼠未出现任何PTS。这些对噪声性听力损失（NIHL）易感性的差异似乎归因于一个与年龄相关听力损失（AHL）的基因。当前的研究旨在确定在表征B6和CB近交系小鼠的噪声强度范围内NIHL的剂量反应曲线。由于对NIHL的敏感性存在相当大的差异，两个品系的噪声暴露仅在110和113分贝处重叠。然而，两个品系呈现出两条不同的剂量反应曲线，相互偏移且斜率不同。我们推测，B6品系小鼠从98至113分贝的PTS呈更线性的增加，这与对某些代谢生理机制的累积效应一致；CB小鼠在113至116分贝之间NIHL的突然转变与耳创伤性结构损伤一致。
