中文摘要：

目的探讨促甲状腺激素（TSH）β剪接变体在甲状腺球蛋白（强）免疫诱发的自身免疫性甲状腺炎小鼠甲状腺中的表达及碘过量对表达的影响，了解TSHβ剪接变体是否参与了自身免疫性甲状腺炎发生的病理过程。方法选7～8周龄的BALB／c小鼠48只，雌雄各24只，体质量20—25g。根据小鼠的体质量和性别，采用随机数字表法分为4组，每组12只，雌雄各半。对照组：饮去离子水；免疫（TG）组：饮去离子水，每只小鼠在8周龄时注射0．1mgTg皮下免疫，分别在11周龄和15周龄时各加强免疫1次；高碘（HI）组：饮用0．05％碘化钠（NaI）水；联合（TG＋HI）组：饮0．05％NaI水，免疫同TG组。喂养8周后处死小鼠，采集外周血，通过化学免疫发光法测量血清中总甲状腺素和游离甲状腺素（TT4、FT4）、总三碘甲腺原氨酸和游离三碘甲腺原氨酸（TT3、FT3）水平；取小鼠甲状腺，冰冻切片后用于HE染色，光镜下观察甲状腺细胞形态改变。SYBRGreen荧光实时定量（RT）-PCR检测TSHβ剪接变体表达。结果肉眼下，与对照组比较，HI组和TG＋HI组小鼠甲状腺明显肿大，颜色暗红。光镜下，对照组小鼠甲状腺滤泡大小较一致，上皮细胞多呈立方形，滤泡腔内含丰富胶质，无淋巴细胞浸润；TG组甲状腺滤泡较一致，上皮细胞立方形，可见单个散在淋巴细胞；HI组可见甲状腺滤泡胶质蓄积性扩张，上皮细胞呈低立方状或扁平状，但少见淋巴细胞浸润；TG＋HI组甲状腺内多为胶质蓄积性大滤泡，上皮细胞扁平状，可见滤泡结构破坏及局部淋巴细胞浸润。小鼠FT3、FT4、FT4和TSHβ剪接变体表达组间比较差异有统计学意义（F=4．00、12．54、31．92、214．29，P均〈0．05）。与对照组比较，TG组TT3、TT4、FT4和TSHβ剪接变体表达升高（nmol／L：0．92±0．07比1．30±0．33、67．75±11．91比95．60±14．10；pmol／

英文摘要：

Objective To investigate the expression of marrow-derived thyroid stimulating hormone β（TSHβ） splice variant in thyroid of mouse with autoimmune thyroiditis induced by thyroglobulin （Tg） immunization, and to analyze whether TSHβ splice variant participated in the pathological process of autoimmune thyroiditis. Methods Using random number table, forty-eight mice（24 females and 24 males） Of 7 to 8 weeks old with body mass 20 to 25 g were randomly divided into 4 groups（12 females and 12 males in each group） based on body weight and gender. The control group： fed with deionized water; the Tg-treated group（TG） ： fed with deionized water, and immunized subcutaneously with 0.1 mg Tg at 8 weeks old, boost immunized twice at 11 and 15 weeks old, respectively; the high iodine-treated group （HI）： fed with deionized water containing 0.05% sodium iodide （NaI）;the Tg combined with HI group （TG ＋ HI ： fed with deionized water containing 0.05% NaI, and immunized the same way as the TG group did. Peripheral blood was collected after 8 weeks treatment, which was used for determination of total tetraiodothyronine （TT4）, free tetraiothyronine（FT4）, total triiodothyronine （TT3） and free triiodothyronine （FT3） with chemiluminescence immunoassay （CIA）; thyroid glands were collected to examine the expression of TSHβ splice variant with SYBR Green fluorescent quantitative real-time PCR, and frozen sections were HE stained for observation of histopathological changes of thyroid cells under light microscopy. Results Under naked eyes, the thyroid gland enlarged significantly, and looked dark red in HI and TG ＋ HIgroups. Under an optical microscope, thyroid follicular epithelial cells presented cuboidal, with abundant cytoplasm, presented abundant glial in follicular cavity, without lymphocyte infiltration in the control group; in TG group, the thyroid follicular epithelial cells presented cuboidal, with some single scattered lymphoeytes; in HI group, colloid volume expansion