大鼠顿挫性眼外伤所致白内障动物模型中晶状体上皮细胞IKKα的表达

Expression of IκB kinase-alpha in the lens epithelia cells of cataract which induced by contusion in rat model

目的探讨大鼠顿挫性眼外伤后白内障晶状体上皮细胞(LECs)IκB激酶-α(IKKα)的表达。方法将50只Wister大鼠随机分为5组,每组10只。为A组(钝挫伤3d组)、B组(钝挫伤6d组)、C组(钝挫伤9d组)、D组(钝挫伤12d组)和E组(正常对照组)5组。右眼为实验眼,左眼为对照眼。使用20g铁球20cm高度拍打眼球100次。选取晶状体混浊的大鼠于模型制作完毕后3、6、9及12d处死动物,撕取晶状体前囊膜,免疫组织化学方法检测LECsIKKα的表达定位。结果A、B、C、D组大鼠对照眼LECs中,IKKα于胞浆中呈阳性表达,表现为棕黄色颗粒均匀分布于胞浆中。实验眼LECs中,IKKα亦表现为均匀分布的棕黄色颗粒,A组胞浆及胞核内阳性表达较为显著,B组仍能检测到IKKα与胞浆及胞核内的显著阳性表达;C组IKKα于核内表达减弱;D组已检测不到该激酶核内表达;阴性对照组中未见IKKα棕黄色颗粒表达。结论在眼球顿挫伤所致白内障过程中,IKKα作为核转录因子蛋白-κB(NF-κB)的激活因子,其激活作用不仅仅限于在胞浆内启动NF-κB的水平,而可以直接进入细胞核,甚至可能直接参与基因水平炎症损伤过程。

Objective Ocular contusion cataract is one of the common complications after the contusion of eye with the incidence 24.5%. Present study was to investigate the expression of IκB kinase-alpha （IKKα） in the lens epithelial cells of cataract after eye contusion. Methods Fifty normal Wistar rats were randomized into group A, B, C,D and E. Group A to D was divided according to the different killing time and 10 rats for each group. Group E was the negative group（ 10 rats）. The contusion model was established by striking the right eyes of rats with a steel ball of 20 g from the height of 20 cm for 100 times and the normal left eyes were as controls. The opcified lens from experimental rats were harvested at 3,6,9 and 12 days following hitting. Immunohistochemistry staining was used to assay the expression of IκB kinase-alpha （IKKα） in lens epithelial cells. Results In all the control eyes,the expression of IKKα was seen in the cytoplasm of lens epithelial cells, presenting the buffy particles. However,in the contusion eyes, IKKα was experssed in both cytoplasm and cellular neucleus of lens epithelial cells. Expression level of IKKα peaked in 3 days after hitting and decreased gradually 9 days later and presented the absent expression in the nucleus of lens epithelial cells in 12 days. No any expression of IKKα was found in the negative control group. Conclusion IKKα play an important role in pathogenesis of contusion cataract through activating nuclear factor-κB（NF-κB） in cytoplasm and therefore inducing a inflammatory reactions. IKKα work as a special factor and start the inflammatory reactions in the gene level directly.