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目的观察顺铂对耳蜗微音电位（ｃｏｃｈｌｅａｒｍｉｃｒｏｐｈｏｎｅ，ＣＭ）、总和电位（ｓｕｍｍａｔｉｎｇｐｏｔｅｎｔｉａｌ，ＳＰ）及复合动作电位（ｃｏｍｐｏｕｎｄａｃｔｉｏｎｐｏｔｅｎｔｉａｌ，ＣＡＰ）的影响及毛细胞形态学改变。方法用人工外淋巴液和顺铂灌流豚鼠耳蜗，分别记录耳蜗第三回中阶的ＣＭ、－ＳＰ及ＣＡＰ，琥珀酸脱氢酶染色观察毛细胞的数量变化，透射电镜观察外毛细胞结构。结果顺铂灌流１ｈ：≤６０ｄＢＳＰＬ声强级刺激时ＣＭ、－ＳＰ和ＣＡＰ幅度均较灌流顺铂前略下降，≥７０ｄＢＳＰＬ声强级刺激时幅度比灌流顺铂前明显升高；９０ｄＢ刺激ＣＭ平均升高３．６ｍＶ（Ｐ＜０．０１），ＣＡＰ平均升高０．２３ｍＶ（Ｐ＞０．０５）；１２０ｄＢ刺激时－ＳＰ平均升高１．６ｍＶ（Ｐ＜０．０５）。顺铂灌流２ｈ：４０～９０ｄＢＳＰＬ声刺激３种电位幅度均明显下降。琥珀酸脱氢酶染色的耳蜗铺片表明：灌流人工外淋巴液内、外毛细胞的琥珀酸脱氢酶活性正常；灌流顺铂２ｈ后，外毛细胞的琥珀酸脱氢酶活性下降，内毛细胞正常。透射电镜观察发现：灌流顺铂后外毛细胞胞核染色质消失，线粒体变性，数量减少；内毛细胞结构正常。结论这种耳蜗电位的异常增长可能是由于Ｃａ２＋?
Objective To observe the effects of cisplatin on the cochlear microphones (CM), the summative potential (SP) and the compound action potential (CAP) of the cochlea and the morphological changes of the hair cells. Methods The guinea pig cochleas were perfused with artificial perilymph and cisplatin respectively. CM, -SP and CAP in the third middle stage of cochlea were also recorded. The number of hair cells was observed by succinate dehydrogenase staining. The structure of the outer hair cells was observed by transmission electron microscopy. Results Cisplatin perfusion 1h: ≤60dBSPL amplitude of stimulation of CM, -SP and CAP amplitude than perfusion cisplatin slightly decreased, ≥ 70dBSPL sound intensity level stimulated significantly increased compared with perfusion cisplatin; 90dB stimulated CM average rise (P <0.01). The average CAP was increased by 0.23 mV (P> 0.05). The mean increase of -SP was 1.6 mV (P <0.05) at 120 dB stimulation. Cisplatin perfusion 2h: 40 ~ 90dBSPL acoustic stimulation of three kinds of potential amplitude were significantly decreased. Succinate dehydrogenase-stained cochlear implants showed that the activity of succinate dehydrogenase in outer and outer hair cells was normal in perfused artificial perilymph, and the activity of succinate dehydrogenase in outer hair cells decreased after intraperitoneal injection of cisplatin for 2 h Hair cells normal. Transmission electron microscopy showed that the chromatin of outer hair cells disappeared after perfusion of cisplatin, mitochondrial degeneration and number decreased, and the structure of inner hair cells was normal. Conclusion This abnormal increase in cochlear potential may be due to Ca2 +?