X射线和^(60)Coγ射线辐照食管癌细胞的拉曼光谱研究

Raman Spectroscopic Study on EC9706 cells Irradiated by X-ray and ^(60)Co γ-ray

食管癌细胞(EC9706)经不同剂量X射线和60Coγ射线辐照后继续培养24h,利用激光拉曼光谱分析EC9706细胞内部蛋白质、核酸、脂类等生物大分子的构象和含量变化。分析发现,两种放射源各剂量组拉曼光谱的峰强和频移与空白对照组之间都存在较大的差异。主要表现为(1)X射线辐照后,对照组光谱中存在的某些谱带,个别剂量组中该谱带却消失。蛋白质主链中骨架C-N振动引起的1114 cm-1谱带在各剂量组中普遍消失,膜脂中膜结合β-胡萝卜素的C=C振动谱带1523 cm-1仅存在于6Gy组。(2)60Coγ射线辐照后,蛋白质酰胺Ⅲ带在中等剂量(4、5Gy)组中β折叠结构向无规卷曲转化,大剂量组中DNA中的磷酸二酯(O-P-O)基团的非氢键化程度增强。拉曼特征峰在不同剂量组中的变化,为进一步从物理能级结构角度研究X射线和60Coγ射线对EC9706细胞的辐照损伤机制提供了实验依据。

Raman spectroscopy was used to study the conformation and content changes of protein,nucleic acid and fat,of esophago cells（EC9706） irradiated by X-ray and 60Co γ-ray and cultivated for 24h.The results showed that there were big differences in spectrol intensity and frequency shift between each exposure group and control group.After being irradiated by X-ray,existing some bandes in the control group,disappeared in some dose groups’.The peak at 1114 cm-1 of ν（C-N） in the skeleton chain of protein disappeared in all dose groups.After being irradiated by 60Co γ-ray,βfolder of Amide Ⅲ changed into disordered conformation in the middle dose（4,5Gy） groups and the non-hydrogenation of νs（PO-2） was strengthened due to big dose γ-ray irradiation.This gaves experimental evidence to the study on EC9706 cells’ mechanism of radiation damage by X-ray and 60Co γ-ray in the single of physical-level structure.