硒性白内障模型与人老年性白内障比较研究

Difference between human senile cataract and sodium-selenite-induced cataract

目的比较人老年性白内障和硒性SD大鼠核性白内障,探讨该白内障模型在运用于对人老年性白内障的研究中的可行性,进而初步研究蛋白质变性过程中二级结构的变化。方法15d龄SD大鼠,经皮下注射2mmol·L-1亚硒酸钠溶液建立白内障模型,通过对蛋白含量的测定,蛋白多肽成分的分析以及蛋白圆二色性的检测,对两者进行比较。结果15d龄SD大鼠皮下注射2mmol·L-1亚硒酸钠溶液4d后晶状体出现明显的乳白色核性混浊;与人老年性白内障晶状体相比较,硒性SD大鼠中LMW的蛋白含量亦明显减少;PAGE电泳中出现与人老年性白内障位置相似的电泳条带,SDS-PAGE中的电泳条带差异较大;其CD谱波形与人晶状体蛋白的波形十分相似。结论硒性SD大鼠白内障模型与人老年性白内障在发生过程中产生了相似的变化,该模型可以应用到人老年性白内障的研究中。并初步探讨人老年性白内障发生过程中蛋白变性过程。

Objective To discuss whether the sodium-selenite-induced cataract is a suitable model in the study of human senile cataract and further investigation the change of the conformation of the secondary structure of the protein during the cataractogenesis. Methods A single subcutaneous injection of sodium selenit was given to 15-day old SD rats to produce the model. And it was compared with human senile cataract in three aspect include the content, component of polypeptide and the conformation of the secondary structure of the protein. Results The cataractous model was established four days after the injection. In comparison with human senile cataract, the sodium-selenite-induced cataract has the same change of LMW content, PAGE picture and CD spectrum. But the SDS-PAGE was different. Conclusion The pathogenesis of the sodium-selenite-induced cataract coincide with that of the human senile cataract in that three aspects. It can be used in the study of human senile cataract. And we also discuss the progress of the protein degeneration during the senile cataractogenesis.