长期低硒、低碘对发育期大鼠肝脏和全血GSH-Px活性的影响

Effects of Long-term Selenium and Iodine Deficiency on Glutathione Peroxidase Activities in Blood and Liver of Rats at Embryo Development Stage

[目的]研究长期低硒、低碘对子代发育期大鼠谷胱甘肽过氧化物酶(GSH-Px)活性的影响。[方法]选取人工低硒低碘饲料喂养繁殖的SD大鼠动物模型的仔三代4日龄(F3P4)和21日龄(F3P21)、仔四代4日龄(F4P4)和21日龄(F4P21)共4个时间点的发育期仔鼠为研究对象,采用DTNB直接法对其全血和肝脏GSH-Px活性进行了测定。本模型分4组:①对照组(Control)、②低硒组(Se^-组)、③低碘组(I^-组)、④低硒低碘组(Se^-+I^-组),分别持续喂以不同硒碘水平的人工饲料,饲养繁殖至仔四代。[结果]各时间点内,肝脏和全血GSH-Px活性Se^-组、Se^-+I^-组均显著低于相应对照组、I^-组(P<0.01,肝脏GSH-Px降至相应对照组水平的约1%,全血降至约20%);Se^-组与Se^-+I^-组及I^-组与对照组之间差异无显著性(P>0.05)。Se^-组、Se^-+I^-组同日龄同组内F3代与F4代比较,肝脏GSH-Px活性均表现为F4代显著低于F3 代(P<0.05);全血GSH-Px活性则仅表现出21日龄时F4代显著低于F3代(P<0.05)。[结论]长期低硒、低硒联合低碘会极大降低大鼠发育期机体的GSH-Px活性,其损害在母体内就已发生,子代较亲代损害更重。单纯低碘对其影响并不明显。本实验中的人工低硒低碘饲料喂养繁殖的SD大鼠动物模型在生长发育期的建立和维护也是成功的。

[Objective] To study the effects of long-term deficiency of selenium （ Se ） and iodine （ I ） on the activities of glutathione peroxidase （ GSH-Px ） in rats at embryo development stage. [Methods] Healthy SD rats were divided into 4 groups at random, including control group, Se-deficient group（ Se^- group ）, I-deficient group （ I^- group ） and both Se-and I-deficient group （ Se^-I^- group ）.The rats in each group were given the different man-made feeds containing different levels of Se and I and raised by the time of the fourth generation. The third generation rats with the age of four days （ F3P4 ）, 21 days （ F3P21 ） and the fourth generation rats with the age of four days （ F4P4 ）, 21 days （ F4P21 ）were chosen as four time points of research subjects, the GSH-Px activities in blood and liver were determined by DTNB method. [Results] At each research timepoints, the CSH-Px activities in blood and liver in Se^-group, Se^-I^- group were obviously less than those in the control group and I^- group（ P 〈 0.01, compared with the control group, the GSH-Px activities made up only 1% in liver and 20% in blood ）. There was no significant difference between Se^- group and Se^-I^- group and also no significant difference between I^- group and control group（ P 〉 0.05 ）. There was no significant difference between the F4 and F3 rats in control and I^- group with the same day age. However, in Se^- group and Se^-I^- group, the GSH-Px activities of F4 rats were lower than those of F3 rats with the age of both 4 and 21 days in liver, while the GSH-Px activities of F4 rats were less than those of F3 rats with only the age of 21 days in blood. [Conclusion] Long-term deficiency of Se or both Se and iodine would greatly reduce the GSH-Px activities of rats at the development stage, this had happened in uterus and damaged the offspring generation severely. The deficiency of only iodine had no obvious effects. The SD rats models with prolonged Se, I deficiency were established and maintained successfully at the development stage.