碘摄入量对大鼠钠/碘转运体分布及表达影响

Effects of different iodine intake on distribution and expression of sodium/iodide symporter in rats

目的利用组织芯片分析钠/碘转运体(Na+/I-symporter,NIS)在不同碘摄入量下的大鼠组织器官的分布及表达。方法 Wistar大鼠随机分为3组,分别给予低碘(LI)、正常碘(NI)和高碘(HI)饮食,饲养3个月测定尿碘及制备不同碘摄入量大鼠组织器官的组织芯片,利用免疫组织化学的方法观察NIS的分布和表达。结果 LI组、HI组与NI组大鼠的尿碘含量中位数分别为1.7,305.8,28 056.5mg/L,LI组、HI组与NI组比较差异均有统计学意义(P<0.001);与NI组比较,LI组NIS在甲状腺滤泡上皮细胞基底膜上强表达,而HI组表达较弱;相反,NIS在组肾HI小管上皮细胞基底膜和胞头均有较强表达,而LI组相对较弱表达。结论 NIS不均一性分布于大鼠各组织器官,且碘摄入量可引起甲状腺和肾脏等组织NIS表达量的改变。

Objective To observe the effects of different iodine intake on the dirtribution and expression of sodium/iodide symporter（NIS） protein in rats with tissue microarray.Methods Wistar rats were randomly divided into three groups：low idoine（LI）,normal iodine（NI） and high idoine（HI） based on the iodine levels of the diet.Three months later,urinary iodine was measured and tissue microarray containing 48 spots of rat tissue was prepared.Immunohistochemistry method was used to detect the distribution and expression of NIS protein in different tissues.Results Compared with NI group,urinary iodine was considerably lower in LI group and higher in HI group,paralleling to their iodine intakes.On the other hand,the different iodine intake induced changes of NIS expression in some tissues.The expression of NIS in thyroid follicular epithelial cells was significantly higher in LI group than in NI and HI groups.On the contrary,NIS loacting at renal tubular epithelial cells in HI group strengthened obviously.NIS also distributed in gastric mucosa,intestinal mucosa,glandula angularis and ovaries with no obvious difference among the three groups.Conclusion The findings reveal that there are different expressions of NIS in several tissues of rats.Different iodine intake can cause changes of NIS expression in tissues,especially in thyroid and kidney.