碘对自身免疫性甲状腺疾病大鼠血清与甲状腺组织IP-10 mRNA表达的影响

Effect of iodine on the expression of IP-10 mRNA in serum and thyroid tissue of autoimmune rats

目的探讨碘对自身免疫性甲状腺疾病大鼠血清与甲状腺组织IP-10 mRNA表达水平的影响。方法选取4周龄的特殊清洁级(SPF)级雌性Wistar大鼠90只,按照随机数字法分为对照组(NC)、模型组(TG)、适碘组(NI)、模型组+适碘组(TG+NI)、高碘组(HI)、模型组+高碘组(TG+HI),每组15只。剔除造模失败、死亡、瘦弱的大鼠,选择每组10只。NC组和TG组饮用不含碘的去离子水,NI组合TG+NI组饮用含150μg/L碘的去离子水,HI组和TG+HI组饮用含3 000μg/L碘的去离子水。在第10周结束时处死所有大鼠。放射免疫法(RIA)测定甲状腺自身抗体水平;分光光度计法测定大鼠组织碘和尿碘;酶联免疫吸附试验(ELISA)检测血清IP-10含量;RT-PCR法检测甲状腺组织IP-10 mRNA表达水平。结果 6组大鼠血清的TGAb和TMAb水平及甲状腺组织IP-10 mRNA水平组间比较均差异显著(P<0.05),同等碘处理条件下,模型组的血清水平均显著高于非模型组(P<0.05)。6组大鼠的甲状腺组织碘和尿碘水平组间比较均有显著差异(P<0.05),且随着碘摄入量的增高甲状腺组织碘及尿碘水平均显著升高(P<0.05);同等碘处理条件下,所有模型组的甲状腺组织碘和尿碘水平均低于非模型组。而6组大鼠血清IP-10含量比较无显著差异(P>0.05)。结论大鼠对碘过量具有很强的耐受能力,可以适应高碘现象,当碘过量时,会降低机体甲状腺组织重IP-10 mRNA的表达,以此提高高碘的耐受能力。

Objective To investigate the effect of iodine on the expression of IP-10 mRNA in serum and thyroid tissue of autoimmune rats.Methods 90 SPF female Wistar rats were randomly divided into control（ NC）,model（ TG）,normal iodine（ NI）,model and normal iodine（ TG＋NI） and high iodine（ HI）,model and high iodine（ TG＋HI） groups,15 cases each. NC and TG groups were given no iodine water,NI and TG＋NI groups deionized water containing 150 g/L deionized water,HI and TG＋HI groups water containing 3 000 g/L,NC and TG groups deionized water with out iodine,NI and TG ＋NI groups deionized water containing 150 μg/L of water,HI and TG ＋ HI groups deionized water containing 3 000 μg/L. Radioimmunoassay（ RIA） was used to determine the levels of thyroid autoantibodies; spectrophotometry was used to determine iodine and iodine in rat tissues; enzyme-linked immunosorbent assay（ ELISA） was used to determine serum IP-10 content; RT-PCR method was used to detect the expression of IP-10 mRNA in thyroid tissue.Results The serum TGAb and TMAb levels and thyroid tissue IP-10 mRNA levels were significantly different between two groups（ P〈0.05）; in the same iodine treatment conditions,serum TGAb and TMAb levels of all of the model groups were significantly higher than those of non model groups（ P〈0.05）. The thyroid iodine and urinary iodine levels had significant differences（ P〈0.05）; and with the increase of iodine intake,iodine of thyroid tissue and urinary iodine levels were significantly increased（ P〈0.05）.Conclusions Rats have a strong tolerance to iodine excess,to adapt to the phenomenon of high iodine,when under excessive iodine,it will reduce the IP-10 mRNA expression of thyroid tissue,in order to improve the tolerance of high iodine.