摘要
目的观察Wistar大鼠补充不同剂量碘化钾(KI)对甲状腺抗氧化能力的影响。方法将Wistar大鼠随机分为6组:低碘组(LI),适碘组(NI),5倍高碘组(5HI),10倍高碘组(10HI),50倍高碘组(50HI),100倍高碘组(100HI)。每组20只。按每日进食量和饮水量计算的每日总碘摄入量分别为<1、6.15、30.75、61.5、307.5、615μg/d。喂养6和12个月后,检测甲状腺组织匀浆中的谷胱甘肽过氧化物酶(GPx)活力、超氧化物歧化酶(SOD)活力以及丙二醛(MDA)含量。结果LI组的GPx活力、SOD活力和MDA含量于摄碘6个月时,均较NI组显著增高,差异均有统计学意义(P<0.01)。5HI、10HI和50HI组的GPx活力和SOD活力在摄碘6个月和12个月时与NI组比较,差异均无统计学意义(P>0.05);100HI组的GPx活力和SOD活力在6个月时较NI组增高(P<0.05),但在12个月时较NI组降低,差异均有统计学意义(P<0.05)。在摄碘6个月时,100HI组的MDA含量较NI组有增高趋势(P>0.05);但在12个月时50HI和100HI组的MDA含量均较NI组降低,差异均有统计学意义(P<0.05);其他高碘组MDA含量均与NI组差异无统计学意义。结论低碘导致大鼠甲状腺抗氧化系统失代偿,发生过氧化损伤;长期高碘(100HI)会使甲状腺抗氧化酶活力降低,但未出现明显过氧化损伤;大鼠甲状腺的抗氧化系统对高碘有很强的耐受能力。
Objective To study the effect of different iodine intake on the antioxidation of rat thyroid. Methods The rats were divided into 6 groups, low iodide （LI）, normal iodine （NI）, high iodide including five fold （5HI）, ten fold （10HI）, fifty fold （50HI）, one hundred fold （100HI） and given potassium iodide （KI） at different dosages through food respectively. After 6 and 12 months of treatment, the rats were sacrificed respectively and the activity of glutathione peroxidase （GPx）, superoxide dismutase （SOD）, the content of malondialdehyde （MDA） in the thyroid were determined. Results The activity of GPx, SOD and the MDA content in LI group were significantly higher than those in NI group. There was no difference in the SOD and GPx activity and MDA content among NI, 5HI and 10HI groups. The MDA content in 50HI group was lower than that in NI group after treated for 12 months, but no difference was found between them after treated for 6 months. Compared with NI group, the GPx activity, SOD activity and MDA content in 100HI group increased after 6 months of treatment, however, decreased after 12 months of treatment. Conclusion Low iodine intake can induce oxidative damage of the thyroid gland in normal rats, high iodine （100 fold） intake for a long period （12 months） may decrease the activity of anti-oxidases in thyroid without obvious oxidative damage, that shows the antioxidative system of rat thyroid has a tolerance to high iodine intake.
出处
《环境与健康杂志》
CAS
CSCD
北大核心
2006年第6期503-505,共3页
Journal of Environment and Health
基金
国家自然科学基金重点资助项目(30230330)
关键词
碘化钾
抗氧化能力
甲状腺
Potassium iodide
Anti-oxidative capacity
Thyroid
