【摘要】 目的:探讨低碘膳食对大鼠脑组织同源盒基因Nkx-2.2表达的影响,揭示低碘导致脑发育迟滞的可能分子作用机制。方法:雌性Wistar大鼠随机分为2组:低碘组和正常对照组,均饲以低碘饲料,分别饮用去离子水和碘酸钾溶液,3个月后分别取材于孕16天、新生及20日鼠龄低碘及正常仔鼠,实时荧光定量PCR检测其脑组织中Nkx-2.2 mRNA含量。结果:低碘组血清甲状腺激素水平明显低于对照组(P<0.05或P<0.01),建立缺碘Wistar大鼠动物模型。低碘及正常各年龄组的表达水平随着年龄增加表达趋势不一致,但均有明显差别(F=573.68、120.82,P<0.01)。各年龄组低碘及正常大鼠比较,孕16天正常鼠Nkx-2.2表达水平明显高于低碘鼠(t=6.86,P<0.01),而新生及20日龄低碘鼠Nkx-2.2表达水平明显高于正常鼠(t=15.85、10.61,P<0.01)。结论:同源盒基因Nkx-2.2表达差异与低碘导致脑发育迟滞密切相关。更多还原

【Abstract】 Objective:To explore the influence of low-iodine diet on the expression of homeobox gene NKX-2.2 in rat cerebrum tissue,and to explain the possible molecular mechanism of cerebrum development retardation caused by low-iodine.Methods:Female Wistar rats were randomly divided into two groups:Low-iodine group and control group,both fed with low-iodine feed,given the deionized water and KIO3 solution respectively,they were drawn from the 16-day pregnancy,new-born and 20th days old low-iodine and normal age offspring after three months,and detect the content of NKX-2.2 mRNA in the cerebrum tissue by Real-time fluorescence quantitative PCR techniques.Results:The thyroid hormone levels of low-iodine group in serum were significantly lower than the control group(P<0.05 or P<0.01),establish the model of iodine deficiency Wistar rats.Compared with low-iodine rats of several ages,the expression of Nkx-2.2 have significant differences with the growth of ages(F=573.68,P<0.01),the expression trend of normal group is different but have significant difference among several ages(F=120.82,P<0.01);compared low-iodine rats groups in several ages with normal’s,the 16 days pregnant normal rats have obvious higher level of Nkx-2.2 expression than the low-iodine rats(t=6.86,P<0.01),while the Nkx-2.2 of new-born and 20 days old low-iodine rats express much higher than normal rats(t=15.85、10.61,P<0.01).Conclusion:The difference in the expression of Nkx-2.2 is highly related to the brain development retardation caused by low-iodine.更多还原