Abstract: ObjectiveTo study the effect of KIO3 on liver anti-oxidative capability.MethodsThe rats were divided into 6 groups and given by different dosage of KIO3 with low iodide(LI),normal iodide(NI),5 folds high iodide(5 HI),10 folds high iodide(10 HI),50 folds high iodide(50 HI)and 100 folds high iodide(100 HI).3,6 and 12 months later,the rats were sacrificed and liver GPx activity,SOD activity and MDA content were measured.ResultsThe GPx activity in LI group was markedly lower than NI group.Furthermore,the MDA content and the SOD activity of LI group was higher than that of NI group.The SOD activity of 10 HI group was higher than that of NI group after administration for 6 and 12 months,but no difference was found after administration for 3 month.The SOD activity of 50 HI and 100 HI groups were higher than that of NI group after administration for 3 months,but lower than that of NI group after administration for 6 and 12 months.There was no difference in GPx activity and MDA content between NI group and 4 high iodide groups.ConclusionLow iodide in 2 take would damage anti-oxidative capability of liver in normal rats.There was no obvious oxidative damage to liver in the rats after administration by high iodate for a long period.