碘剂对自身免疫性甲状腺病大鼠甲状腺功能影响

目的观察补充碘剂对自身免疫性甲状腺病大鼠甲状腺功能的影响。方法采用皮下注射甲状腺球蛋白诱发实验性自身免疫性甲状腺炎动物模型(EAT),通过饮水中给予碘剂观察对大鼠甲状腺重量、形态学改变、促甲状腺激素(TSH)和甲状腺激素谱以及甲状腺自身抗体滴度变化。雌性Wisrar大鼠分为A空白对照组、B抗原免疫组、C碘剂喂养组及D抗原免疫加碘剂组。免疫组大鼠给予猪甲状腺球蛋白100μg/只,与全弗氏佐剂(CFA)乳化后皮下注射,第2周后给予不完全弗氏佐剂(IFA)乳化抗原加强免疫。碘剂干预组给予0.05%碘化钠溶液喂养。分别于第0,2,4,6,8周内眦静脉采集血样。结果D组甲状腺绝对及相对重量显著高于A、B组。P<0.05,略高于C组;C组高于A、B组,但P>0.05。B组小叶间散见淋巴细胞浸润;碘剂组滤泡异质性改变,小叶间少量淋巴细胞浸润;D组甲状腺滤泡灶性萎缩、炎症细胞浸润明显,范围较广,滤泡周围可见纤维组织增生。第8周B组FT3、FT4高于A、B组;D组升高更为显著。P<0.01。B组大鼠血清TgAb、TmAb自第2周开始升高,至第4周达到最高水平,随后略有下降,但仍然显著高于对照组;C组抗体水平缓慢升高,第8周时升高达到高峰;D组抗体水平升高最快,而且维持时间更长,P<0.01。结论碘剂可以加重EAT大鼠甲状腺病理损害,升高甲状腺自身抗体滴度,

Effect of iodine on immune disorder and thyroid function in EAT rats

Objective To investigate the effect of high iodine uptake on the changes of thyroids weight,morphology,thyroid hormaone,thyroid stimulating hormone(TSH)and thyroid autoantibodies..Methods Female Wistar rats were divided into four groups:A:normal control,group B:porcine thyroglobulin immunized,group C:iodine water raised,group D:combined with iodine taking and immunization.EAT rat was immunized with PTg 100ug emulsificated with CFA,then was injected subcutaneously with PTg 100ug emulsificated with IFA after 2 th wk.Rats in group C and D were raised with 0.05% Nal water.Blood samples were taken at 0,2,4,6,8 th wk.Results Absolute and relative weight of thyroids in group D were heavier than those in groups A and B,P<0.05.Medium lymphocyte infiltration in thyroid tissue presented in group B,Severe infiltration,proliferation of fibrous tissue and local fulliclar atrophy showed in group D.FT_3 and FT_4 value in group B increased at 8 th wk,but is lower than that in group D,P<0.01.TgAb and TmAb of group B rose at 2 th wk and reached to the peak at 4 th wk,then descended a little but still higher than that in group(P<0.01).The autoantibodies in group C stepped up gradually and reached the peak value at 8 th wk.The titer of TgAb and TmAb in group D rose most quickly and lasted for longest time than in other groups.Conclusion Iodine may deteriorate Tg-induced autoimmune thyroiditis,enhance the destruction of thyroid gland and elevate the level of autoantibodies.Excessive iodine intake can worsen worsen experimental autoimmune thyroiditis.