40Hz听觉相关电位测试在耳毒性试验中的应用

40-Hz Auditory event related potential audiometry used for ototoxicity experiment

对杂色豚鼠（性别不拘）每天经鼓室植管法应用１％庆大霉素（ＧＭ）连续七天。全身麻醉后电测听诱发４０Ｈｚ听觉相关电位（４０ＨｚＡＥＲＰ）测试各动物耳蜗功能，给药前及最后一次给药后均测４０ＨｚＡＥＲＰ听阈，用短纯音１０００Ｈｚ刺激，由ＫＧＴ－Ⅱ型脑干反应测听仪检测。结果证明：用药前平均阈值为３５．７±５．７２。用ＧＭ七天后，出现听力损失，振幅明显降低，平均阈值为５８．５７±１１．７，两组间听阈差异有非常显著意义（Ｐ＜０．０１）。两组间的阈移及振幅可用Ｗｉｌｃｏｘｏｎ两组比较法或Ｔ检验法分析比较，本实验研究结果证明４０ＨｚＡＥＲＰ测试法是值得推荐的一种听力测定法。

For seven consccutive days,both male and femalc pigmentcd guinea pigs receivcd, under gencral anasthcsia,ototopical applications of 1% gentamyein(GM) through a tube implanted in tympanic cavity.Heating thresholds were measured before and after the last application of the drug.The coehlcar function of each animal was monitored by evoked brainstem response aud iomctry.Acoustie band clicks of 1000Hz werc generated by NGT-Ⅱauditory brainstem response audiometry equipment.The findings rcvcaled that the hearing thresholds of normal cats wcre 35.7±5.72 db nHL on avetage and that after administration of 1% GM were 58.57±11.7 db nHL on avcrage.The obvious losses in hearing thrcshold could be seen after sevcn day GM application.Comparing the hearing losscs could revcal the differences in preadministration group with the group after 7 days application(P<0.01).Pairtcd valucs comparing the shift of hearing thrcsholds and amplitudeE betwecn diffcrent groups were analyzcd by the Wilcoxon pair-signed rank test or T-test.The invcstigation come to the conelusion that 4OHz AERP is a very good audiometry method and should be valuable to be recommended.