过度光照后诱导型一氧化氮合酶在大鼠视网膜色素上皮的表达

Expression of inducible nitric oxide synthase in retinal pigment epithelium of rat after overwhelming light exposure

目的探讨过度光照诱导大鼠视网膜色素上皮(retinalpigmentepithelium,RPE)细胞表达诱导型一氧化氮合酶(induciblenitricoxidesynthase,iNOS)的作用及其病理学意义。方法应用免疫组织化学的方法分别检测处于自然光照环境中的正常大鼠及接受强光过度照射后大鼠的视网膜RPE细胞中iNOS的表达情况。结果正常大鼠RPE细胞中未见iNOS的表达,而过度光照后大鼠RPE细胞的胞浆中表达高水平的iNOS,同时视网膜外核层感光细胞发生结构损伤。结论过度光照可诱导RPE细胞表达iNOS,这一异常改变可能是视网膜感光细胞结构损伤的重要原因。

Objective To investigate the expression of inducible nitric oxide synthase （iNOS） in retinal pigment epithelium （RPE） of rats induced by overwhelming light exposure and its pathologic meaning. Methods The immunoreactive activity of iNOS in RPE of normal rats in natural light environment and those exposed to constant white intensify light were detected with immunohistochemistry assay respectively. Results The expression of iNOS was not seen in RPE of normal rats, whereas significantly high immunoreactive activity of iNOS in RPE as well as structure destroy of photoreceptors were established after overwhelming light exposure. Conclusion The expression of iNOS could be induced by overwhelming light exposure and this abnormal change might play an important role in light-induced damage of photoreceptors.