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目的：为探讨脑缺血再灌注对大鼠耳蜗形态学及听觉的影响。方法：采用闭塞大鼠四动脉脑缺血模型，观察了脑缺血３０分钟及再灌注不同时间大鼠耳蜗结构和听阈的动态变化，形态学观察应用光镜、扫描电镜与透射电镜，听力测定采用 ４０Ｈｚ听觉相关电位（４０ Ｈｚ ＡＥＲＰ）技术。结果：缺血 ３０分钟和再灌注 ２小时、２４小时、７２小时 ４０Ｈｚ ＡＥＲＰ反应阈与缺血前比较显著提高（Ｐ＜０．０１），随再灌注时间延长听阈逐渐降低。病理变化特点是再灌注期间Ｃｏｒｔｉ’ｓ器部分外毛细胞缩短、肿胀或坏死，听毛紊乱、脱落；螺旋神经节神经元数目减少；线粒体水肿变性，内质网高度扩张、囊泡变。再灌注７天后，听力和细胞损伤逐渐恢复。结论：脑缺血再灌注可致突发性听力下降和耳蜗细胞损伤，该研究为缺血性内耳损伤的防治提供了实验依据。
Objective: To investigate the effects of cerebral ischemia-reperfusion on morphology and hearing of the rat cochlea. Methods: The occlusion rat model of four-artery cerebral ischemia was used to observe the dynamic changes of cochlear structure and auditory threshold at 30 minutes after cerebral ischemia and at different times of reperfusion. Morphological observation was observed with light microscope, scanning electron microscope, transmission electron microscope, 40Hz AEP (40 Hz AERP) technique was used. Results: The threshold of 40 Hz AERP at 30 min after ischemia and 2 h after reperfusion was significantly higher than that before ischemia at 24 h and 72 h (P <0.01). The threshold of hearing threshold decreased gradually with the reperfusion time prolonged. Pathological changes are characterized by shortening, swelling or necrosis of part of the outer hair cells of Corti’s device during reperfusion, and disorganization of the auditory hair; decrease in the number of spiral ganglion neurons; mitochondrial edema degeneration, high endoplasmic reticulum expansion and vesicle change. After 7 days of reperfusion, hearing and cell damage gradually recovered. Conclusion: Cerebral ischemia-reperfusion can cause sudden hearing loss and cochlear cell injury. This study provides experimental evidence for the prevention and treatment of ischemic inner ear injury.