摘要
目的建立诱发型实验性自身免疫性甲状腺炎(EAT)动物模型,研究碘对诱发EAT形成的影响,进一步探讨其可能的作用机制。方法:采用雌性Lewis大鼠诱发EAT并饲以不同碘含量的饮食,观察各组大鼠甲状腺病理改变、血清中Tg自身抗体水平、血清中甲状腺激素水平、脾细胞分泌TNF水平和甲状腺FasmRNA表达水平。结果1.诱发EAT的HI组大鼠炎症范围较广,为较重度炎症。NI组显示为轻度炎症,且为恢复期。LI组显示为滤泡内少量淋巴细胞浸润。2.诱发EAT的HI、NI和LI组大鼠血清中均出现较高水平的Tg自身抗体,3组间无显著性差异。3.诱发EAT的HI组大鼠脾细胞分泌TNE水平高于NI和LI组(P<0.05)。4.诱发EAT的HI、NI和LI组大鼠甲状腺FasmRNA的表达水平均较各自未诱发EAT的大鼠明显升高,其中HI组高于同组的NI和LI组,P<0.01。结论1.高碘饮食可使已诱发EAT的Lewis大鼠甲状腺组织炎症加重且炎症反应持续时间较长,考虑与脾细胞分泌的TNF水平和甲状腺FasmRNA的表达水平较高有关。2.未发现甲状腺组织炎症的程度与自身抗体水平相关。
Objective To establish an induced EAT(Experiment Autoimmune Thyroiditis)model and investigate the ef-fects of dietary iodine on the induction of AITD and the mechanisms involv ed.Methods Lewis rats,fed by different dietary io-dine,were passively immunized with Wistar rats' Tg simultaneously.Two months follo wing the last immunization,patholo gical changes in thyroid tissue,anti -Tg a utoantibodies' titer in sera,the level of TNF secreted by splenic cells,thyroid hormones' level in sera and the expression of Fas mRNA in thyroid tissue were examined.Results①Induced EAT rats from HI group had a wider inflammatory range(3～4times as NI group),indicating a severe inflammation i n thyroid glands,while rats from NI g roup showed a mild inflammation in restoration stage of thyroid glands and those from LI group just showed a light ly mphocytic infiltrat-ing in follicles.②Higher titers of anti -Tg autoantibodies appeared in the sera of induced E AT rats from HI,NI and LI groups,but no statistical significant diff erence could be found between them.③The level of TNF secreted by splenic c ells in induced ETA rats from HI group was much higher than those from NI and LI groups(P<0.05).④The expression of Fas mRNA in thyroid tis-sue of induced EAT rats from HI,NI and LI groups was significantly increased respectively comparing with those that were not in-duced from each group.Furthermore,the expression of Fas mRTA in induced EAT rats from HI group was much higher than those from NI and LI groups(P<0.01).Conclusions ①High iodine diet could aggravate the inflammatory reaction in thyroid glands of Lewis rats after induction,which may be related to the high level of TNF secreted by splenic cells and the exp ression of Fas mR-NA in thyroid tissues.②No clear relationship between the extent of inflammation in the thyroid g lands and the titer of anti -Tg autoantibody can be found.
出处
《中国地方病防治》
2002年第5期267-271,共5页
Chinese Journal of Control of Endemic Diseases
基金
国家自然科学基金资助项目(部分内容)批准号:30070676
