豚鼠耳蜗缺血再灌注损伤后iNOS活性与细胞凋亡关系

目的：探讨椎基底动脉缺血再灌注耳蜗组织损伤方式及可能的损伤机制。方法：健康豚鼠72只，随机分成正常组、假手术组、模型组，每组各8只。用组织化学方法观察缺血再灌注不同时间耳蜗各部位的组织改变；用免疫组织化学法（ABC）检测各组动物耳蜗中诱导型一氧化氮合酶的表达和变化；用原位凋亡法（TUNEL法）观察耳蜗的细胞凋亡情况。结果：缺血再灌注的内外毛细胞变形缺损、血管纹变薄等；诱导型一氧化氮合酶在缺血及再灌注的表达增强；正常组及假手术组没有或仅有个别部位出现细胞凋亡，缺血及再灌注各组内外毛细胞及螺旋神经节部位凋亡细胞明显增多。结论：再灌注期间细胞凋亡数较缺血期间明显增多，其原因为包括一氧化氮在内的多种氧自由基表达增高所致。

Expression of inducible nitric oxide synthase and cell apoptosis in cochlear of guinea pigs after ischemia-reperfusion injury

Objective: To observe the change of cochlear after ischemia reperfusion in different time and analysis the expression of iNOS. Methods: 40 healthy guinea pigs were devided into the normal group, negative control group and model group. Every groups have 8 guinea pigs. The hismorphology of cochlear was observed with hemotoxylineosin (HE) staining. The iNOS immunoactivity in cochlear was studied by immunohistochemisty and labeling ratio of iNOS expression was studied by image analysis. The cell apoptosis was studied by TUNEL. Results: Lesions were detected in the hair cell and the stria vascularis in ischemia and reperfusion groups. Labeling ratio of iNOS expression increased in the ischemia and reperfusion groups. There were more cell apoptosis of the hair cell and the screw ganglion in the ischemia and the reperfused groups. Conclusions: Number of the cell apoptosis in the reperfused were more than those the ischemia groups, Because Labeling ratio of the oxygen free-groups including NO expression was increased in the reperfused.