目的观察昆明小鼠补充不同剂量碘酸钾(KIO3)对脑抗氧化能力的影响。方法将160只昆明小鼠随机分为4个剂量组:适碘组(NI),5倍高碘组(5HI),10倍高碘组(10HI),50倍高碘组(50HI);每组再分为雌雄两个组。各组动物均饲以正常鼠饲料(平均碘含量为300txg/kg),NI组饮用去离子水,各HI组分别饮用含不同浓度(2023.6、4553.2、24789.6μg/L)碘酸钾的去离子水,每只小鼠每日的总摄碘量依次为1.5、7.5、15、75μg。喂养3和6个月后,检测脑组织匀浆中谷胱甘肽过氧化酶(GPx)活力、超氧化物歧化酶(SOD)活力以及丙二醛(MDA)含量。结果不同剂量组之间比较,50HI组的GPx活力在3和6个月时较同性别的NI组增高,差异有统计学意义(P〈0.05),而50HI组的MDA含量在6个月时较NI组降低,差异有统计学意义(P〈0.05);50HI组的雌性组的GPx活力较雄性组增高,差异有统计学意义(P〈0.05)。结论长期摄入高剂量碘酸钾可诱发小鼠脑组织发生氧应激反应(尤其是雌性),但是并未见对脑组织产生明显过氧化损伤,脑对高碘具有一定的耐受能力和代偿能力,但其耐受和代偿的机制还有待进一步研究。
Objective To study the effect of different high dosage KIO3 on the brain anti-oxidative capability in mice. Methods The mice were randomly divided into eight groups and treated with different doses of KIO3 through drinking water, those were normal iodide (NI), five fold high iodide (5HI), 10 fold high iodide (IOHI) and 50 fold high iodide (50HI), furthermore, each group were divided into two group, male and female. By controlling foodstuff and drinking water (adding different amounts of potassium iodate into water), all groups got prospective iodine intake respectively, with doses of 1.5, 7.5, 15 and 75 μg/d. After three- and six- month treatment, the brain GPx activity, SOD activity and MDA content were measured. Results The GPx activity of 50HI groups was higher than that of NI group after for three- and six-month treatment, but no difference was seen in 5HI and 10HI groups. The MDA content of 50HI group was lower than that of NI group after six-month treatment. There were no difference in SOD activity between NI group and three high iodide groups. Furthermore, the GPx activity of female mice was higher than that of male mice in 50HI group. Conclusion Long term high iodide intake may affect the anti-oxidative capability of brain in normal mice, especially in female, but it will not easy to induce obvious oxidative damage in brain of mice.