Abstract: BACKGROUND ＆ AIM: To Study the dose-effects relationship between Vitamin C(VC), Vitamin E(VE) , and lipid peroxidation with the model of rabbit injured by radiation. MATERIAL AND METHODS: Chinese rabbits were chosen as the experimental animals and were randomly divided into 5 groups. They were negative control group,positive group, and trial groups of VC,VE. The trial groups contained three different dosages of VC and three different dosages of VE. Peanut oil was selected as diluent which had been gotten rid of vit E.The five groups were supplied by injection of vein with the dosages of VC 10 mg/kg, VC 20 mg/kg, VC 30 mg/kg everyday respectively. The three VE groups were supplied by gavages with the dosage of VE 20 mg/kg,VE 40 mg/kg, VE 60 mg/kg, everyday rspectively too. On the third day all groups,except negative control group,were radiated by 60 Co with the dose of 4.5 Gy.Then they were fed as before,and on the sixth day all rabbits were killed,blood and liver were removed for the analysis of changes in catalytic activity of SOD and content of MDA by means of Auto-machine. RESULTS： After the radiation,the catalytic activities of hepatic SOD in radiation groups were higher than those in the negative control group(P<0.01),and trial groups of VC and VE showed some protective effect of rabbit against radiation, and there was a dose-effect relationship between the VC、VE and radiation injury. The content of hepatic MDA in trial group was lower than positive group (P<0.01). They showed some effect of protective effects against increase of MDA,and showed the dose-effect relationship between the dosage of VC、VE and protection against injury of irradiation. CONCLUSION： The effect of individual use of VC、VE has protest effect of SOD catalytic activity and inhibition on MDA which exists dose-effect relationship;The antioxidation of vit.E can not protest against radiation of peripheral blood and immunological cells. When VC and VE were given to rabbits toghter,there was a protective effect on of rabbits injured by radiation of 60Co γ ray.

Key words: SOD, MDA, radiation injury, antioxidation