低碘膳食对大鼠脑组织中同源盒基因NKX-2.2表达的影响  

Effects of Low-iodine Diet on the Expression of Homeobox Gene NKX-2.2 in Rat Cerebrum Tissue

作　　者：张瑞[1] 戈海泽[1] 赵秀娟[1] 李媛[1] 郭刚[1] 

机构地区：[1]天津医科大学代谢病医院,天津300070

出　　处：《中国生物工程杂志》2009年第2期92-96,共5页China Biotechnology

基　　金：国家自然科学基金(30571617)资助项目

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。Objective ：To e 2.2 in rat cerebrum tissue, and xplore the influence of low-iodine diet on the expression of homeobox gene NKX- 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. Ol ）. Conclusion：The difference in the expression of Nkx-2.2 is highly related to the brain development retardation caused by low-iodine.

关 键 词：低碘 同源盒基因 实时荧光定量PCR 脑发育 

分 类 号：Q786[生物学—分子生物学]