CBA、C57BL/6bkl小鼠对脉冲性噪音损伤敏感性的研究

目的研究CBA、C57BL／6bkl小鼠对脉冲性噪音损伤的敏感性。方法小鼠共分为8组，第1、2、3组为CBA小鼠（n分别为9、10、10）分别给予160 dB SPL 50、100、150次脉冲噪音暴露，第4、5、6组为C57BL／6bkl小鼠（n皆为10），分别给予160dB SPL 50、100、150次脉冲噪音暴露，第7、8组为CBA和C57BL／6bkl小鼠对照组（n=10），无噪音暴露。在噪音暴露前、噪音后24h及28d测听觉脑干诱发电位。结果给予160 dB SPL 50次脉冲噪音暴露后，CBA只出现暂时性阈值漂移，C57BL／6bkl出现暂时性和永久的阈值漂移，给予160 dB 100次和150次脉冲噪音暴露后，CBA和C57BL／6bkl均出现暂时性和永久性阈值漂移。对照组无阈值漂移。结论C57BL／6bkl小鼠对脉冲性噪音更敏感。耳蜗铺片形态学亦支持上述结论。

Susceptibility of CBA and C57B/6bkl mice to impulse noise

Objective To observe changes in CBA and C57B/6bkl mice exposed to impulse noise. Methods Seventy nine mice were divided into eight groups. Group1,2 and 3 (CBA mice, n=9,10 and 10 respectively) were exposed to 50,100 and 150 times of 160dB SPL impulse noise. Group 4, 5 and 6 (C57B/6bkl mice, n=10) were exposed to 50,100 and 150 times of 160dB SPL impulse noise. Group 7 and 8 (CBA and C57B/6bkl mice respectively, n=10) were control groups without noise exposure. ABR thresholds were determined prior to, 1 day and 28 days after impulse noise exposure. Results The CBA mice showed only temporary threshold shifts after 50 times impulse noise exposure. In contrast the C57B/6bkl mice showed temporary threshold shift (TTS) and permanent threshold shifts (PTS) after 50 times impulse noise. Both CBA and C57B/6bkl mice showed temporary and permanent threshold shifts after 100 and 150 times impulse noise, while no TTS and PTS were observed in the control groups 28 days after impulse noise exposure. Conclusion The C57B/6bkl mice are more susceptive to impulse noise than those of the CBA mice. Cochlear morphological results further show that the C57B/6bkl mice have severer damage trauma than those of the CBA mice.