过亚硝酸根(ONOO-)具有细胞毒性,能够修饰DNA碱基、造成DNA单链断裂。本文采用HPLC-ECD以及琼脂糖凝胶电泳法分别研究了ONOO-诱导的DNA碱基修饰以及DNA链断裂。结果表明,在一定ONOO-浓度范围内,8-OHdG的生成量以及DNA链断裂程度与其浓度有依赖关系。同时还分别研究了槲皮素、黄酮、α-萘基黄酮、咖啡酸以及含有巯基的谷胱甘肽、硫辛酸等天然抗氧化抑制剂对ONOO-诱导DNA损伤的抑制效果。结果表明,除黄酮、α-萘基黄酮外,其它物质都有明显的抑制作用,其中抑制效果最显著的是槲皮素。 Over-nitrite (ONOO-) is cytotoxic, capable of modifying DNA bases, resulting in single-stranded DNA breaks. In this paper, ONOO-induced DNA base modification and DNA strand breaks were studied by HPLC-ECD and agarose gel electrophoresis. The results showed that the generation of 8-OHdG and the degree of DNA strand breaks were dependent on the concentration of 8-OHdG at a certain concentration of ONOO-. The inhibitory effects of quercetin, flavonoids, α-naphthyl flavonoids, caffeic acid and sulfhydryl-containing glutathione, lipoic acid and other natural antioxidants on ONOO-induced DNA damage were also studied. The results showed that in addition to flavonoids, α-naphthyl flavonoids, other substances have a significant inhibitory effect, of which the most significant inhibitory effect of quercetin.