茶叶对致癌物在诱癌过程中的作用

本文针对3种茶样在抗脂质过氧化方面进行了抗癌机理研究。实验选择Wistar雄性大鼠,用N-甲基苄基亚硝胺(NMBzA)诱发食道肿瘤,分别用杭州炒青、福建花茶及铁观音抑制肿瘤的发生,测定了血浆丙二醛(MDA)、红细胞超氧化物歧化酶(SOD)、过氧化氢酶(CA)、谷胱甘肽过氧化物酶(GSH-Px)。结果发现诱癌大鼠体内SOD、CA活性降低,MDA生成量增加。而诱癌加茶后,体内MDA生成量降低,SOD、CA活性明显增高。表明上述3种茶样具有一定的抗氧化性,它在抑制肿瘤的发生发展过程中起着重要作用。这种抗氧化作用与茶多酚有关。所测茶叶中的茶多酚含量:炒青、花茶、铁观音分别为18.47％、21.71%和10.90％。

The Effect of the Tea on Antioxidation in the Rats Induced Oesophageal Tumor

This paper reports the study of the tea on anticarcinogenesis mechanism in inhibiting oesophageal tumor. The wistar male rats were given Hangzhou Green Tea, Fujian Jasmine and Oolong as drinking water when they were intubated by N-nitrosomethylbenzylamine (NMBzA) to be induced Oesophageal tumor. The lipid peroxidation level in the plasma and the activity of superoxide dismutase (SOD), catalase (CA)and glutathion peroxidase (GSH-Px)in the red cell were determined. Contents of MDA were much higher but the activity of SOD and CA were much lower in the NMBzA-treated rats than in the control. After the rats were given different tea as drinking water with NMBzA, the activity of SOD and CA were elevated and MDA contents were lowered. The result shows that tea contains an-tioxidants and have strong antioxidation. It plays an importment role in inhibiting carcinogenesis. These antioxidants may be related to tea polyphenols. The contents of tea polyphenols in the Fulian Jasmine, Oolong and Hangzhou Green Tea are 21.71%, 10.90%and 18.40% respectively