大白鼠糖致白内障的激光喇曼光谱研究

LASER RAMAN SPECTROSCOPY OF GALACTOSE CATARACT IN RATS

作者用激光喇曼光谱法分析半乳糖导致大白鼠晶状体混浊过程中构象的变化。通过SPEX 1403型激光喇曼光谱仪得到了正常及不同混浊度晶状体的喇曼光谱。结果表明晶状体可溶性蛋白质二级结构的光谱未见异常,其残基酪氨酸及色氨酸微环境起了变化。随着晶状体混浊度的增加,SH谱峰强度变小而S-S键谱峰增强,同时观察到荧光背景逐渐加强。经分析认为晶状体混浊是与蛋白质分子的聚集有关。

In this paper we have described mainly the conformational changes of lens proteins ia galaclose cataract by laser Raman spectroscopy.Eye lens consists of water-soluble protein and waterinsoluble protein. Normal lens has a well-developed waterprotein construction thar efficiently transmits the visible light. When the water-protein structures undergo destructioon, the lens degrades in opacification and undergoes interfarence in vision. That is the cattaracr. Laser Raman spectroscopy has been used as a nondestructive probe to determine the cconformational changes of lens protein during opacification. We have obtained Raman spectra in normal and cataract Wistar rats lenses. Due to the galactose metabolism, lens proteins are subject to biochemical changes. Raman spectra obtained show no difference between normal and opaque lens in the 900-1700 cm-1 spectral region. But the spectra indicated Tyr and Trp microenvironment have changed in 450-900 cm-1 region. In addition, the Raman spectrum in 2578 cm-1 of SH groups decreased and the spectrum in 500 cm-1 of S-S bonds increased with development of opacification. It indicates that the microprotein aggregation is correlated with the cataract formation.