Hep-2细胞经X射线照射后其培养基吸收光谱的研究

Study on Absorption Spectra of Cell Substrate for Hep-2 Cell after Being Radiated by X-Ray

采用日本岛津UV-3101分光光度计测量了受不同剂量X射线照射后继续培养24,48,72 h的人上皮样喉癌细胞株Hep-2的培养基RPMI1640(10%胎牛血清)的紫外吸收光谱,分析了该培养基中蛋白质的紫外吸收特性。结果发现:不同剂量组培养基的吸收光谱存在明显的差别,RPMI1640培养基(10%胎牛血清)原在233 nm处的吸收峰在受照细胞生长过程中位移至235 nm附近,278 nm处的吸收峰随着细胞培养时间的增加而逐渐变的平滑直至消失;各剂量组细胞培养基吸收光谱强度随时间而增加,在细胞受X射线照射后继续培养24,48 h时各组培养基吸收强度均低于空白对照组,但到了第72 h时均超过了空白组,这反映了该培养基中芳香族氨基酸中各种氨基酸(如色氨酸、酪氨酸、苯丙氨酸)的含量及比例变化,说明癌细胞在生长过程中对芳香族氨基酸的改变不是按等量比的。这些改变与X射线照射引起Hep-2细胞的凋亡及坏死程度有密切的关系,这将为研究人喉癌最佳X射线放射剂量奠定基础。

UV-absorption spectra of the Hep-2 cell＇s culture medium RPMI1640（10%Foetal Calf Serum） were collected by UV-3101 spectrophotometer after the Hep-2 cell was radiated by X-ray and cultivated for 24,48 and 72 h,and the absorbability of the proteins in the substrate was analyzed.From these results it was found that there were visible differences among these absorption spectra.In particular,the absorption peaks of the RPMI1640 culture medium during the cultivation shifted from 233 to 235 nm,while the absorption peak at 278 nm became more and more smooth and even finally disappeared with the cultivation time.On the other hand,the absorption intensity of the different-dose groups rose greatly with the time,and were all lower than the control group until the cells were cultivated for 72 h after being radiated by X-ray.It was showed that the content of each amino acid has already changed.That is, during the growing course of the cancer cells,the tryptophan and casein were not depleted equivalently.And there were some important relations between the absorption spectra and the cells＇ apoptosis and necrosis induced by X-ray.This will be a foundation for the study of the best X-ray dose for the larynx carcinoma