顺铂作用下沙鼠耳蜗螺旋神经节神经元和Corti器细胞的凋亡

Cisplatin-induced apoptotic cell death in spiral ganglion and organ of Corti of mongolian gerbil cochlear

目的 探讨顺铂是否可引起沙鼠耳蜗螺旋神经节 (spiralganglion ,SG)神经元和Corti器细胞的凋亡。方法 对沙鼠进行顺铂连续腹腔注射 ,每日 4mg kg体重 ,分别于健康对照组及给药 4、5、6、7d各处死沙鼠 12只 ,取左侧耳蜗 ,每组动物取 10只耳蜗做平行蜗轴的石蜡切片 ,另 2只耳蜗做底回蜗轴及基底膜超薄切片。通过末端脱氧核苷酸转移酶介导的dUTP缺口末端标记技术 (terminaldeoxynucleotidyltransferase mediateddUTPnickendlabelingmethod ,TUNEL)及透射电镜检测连续用药不同时间后底回SG及Corti器的细胞凋亡情况。结果 连续应用顺铂 5～ 7d ,在透射电镜下可以观察到底回SG神经元及外毛细胞中出现凋亡特征性病理改变 ,TUNEL标记的石蜡切片中可见给药 5d后SG和Corti器出现的阳性细胞明显高于健康对照组 ,给药 6～ 7d阳性细胞进一步增加。

Objective To investingate whether apoptosis is one of the mechanism for cell death in spiral ganglion(SG) and organ of Corti of Mongolian gerbils cochlea induced by cisplatin Methods Mongolian gerbils were administered 4 mg kg -1 d -1 cisplatin consecutively for 4 to 7 days The apoptotic cell death in spiral ganglion and organ of Corti of cochlea basal turn was detected via transmission electron microscopy and terminal deoxynucleotidyl transferase mediated dUTP nick end labeling(TUNEL) method Results The observation of electron microscopy shown special morphological change consistent with the feature of cell apoptosis in some spiral ganglion cells and outer hair cells after 5 7 days′ cisplatin treatment The apoptotic labeling by TUNEL in spiral ganglion and organ of Corti was detected after 5 days′ treatment and increased after 6 and 7 days′ treatment whereas almost negative result were obtained in the normal control animals Conclusion Apoptosis is one of the important mechanisms for cell injury of spiral ganglion and organ of Corti induced by cisplatin