中文摘要：

目的研究适碘条件下不同硒摄入水平对实验性自身免疫性甲状腺炎（EAT）大鼠甲状腺细胞凋亡蛋白Fas／FasL表达的影响。方法将32只雌性Lewis大鼠按数字表法随机分成4组，分别设为对照组（C组），模型组（M组），补硒＋模型组（se^＋ ＋M组），低硒＋模型组（Se^- ＋M组），在适碘条件下（含10．90mg／kg）对各组先施加不同水平的硒（Se^＋ ＋M组2mg／kg，C与M组0．20mg／kg，Se^- ＋M组0．02mg／kg）干预2周后，再采用猪甲状腺球蛋白免疫大鼠建立EAT模型，取甲状腺组织制成石蜡切片，采用免疫组织化学检测、比较Fas／FasL表达情况的差异。结果EAT大鼠甲状腺Fas及FasL较对照均出现表达增加，其中Fas的表达有随补硒水平的升高而下降的趋势，Se^＋ ＋M组吸光度值（0．036±0．004）与M组（0．059±0．006）相比，Fas表达明显受到抑制（q=11．591，P=0．000），与Se^- ＋M组（0．050±0．005）相比，Se^＋ ＋M组Fas呈较低表达水平（q=7．055，P=0．000）；但补硒对FasL的表达无明显影响。结论补硒能减少Fas在甲状腺细胞中的表达，对自身免疫性甲状腺疫病的发展具有抑制作用。

英文摘要：

Objective To study the effect of different selenium intake on the expression of apoptosis protein Fas/FasL in experimental autoimmune thyroiditis （EAT） rats＇ thyroid with adequate iodine. Methods Thirty-two female lewis rats were divided stochastically into 4 groups as C group, M group, Se^＋ ＋ M group,Se^- ＋ M group, respectively, and pretreated with feedstuffs containing different concentrations of selenium （ Se^＋ ＋ M group 2 mg/kg, C and M group 0. 20 mg/kg, Se^- ＋ M group 0. 02 mg/kg, respectively） for two weeks, and immunized the rats with porcine thyroglobulin （pTg） to establish an EAT model. The thyroid gland was sampled, embedded in mineral wax and sliced, and the expression of Fas/FasL was measured with immunohistochemistry. Results Both the expressions of Fas and FasL of EAT rats were significantly increased as compared with control group. The expression of Fas in rats＇ thyroid follicular cells with EAT was down-regulated as the increased selenium intake （optical density： 0. 059 ± 0. 006 ）, the expression of Fas of Se^＋ ＋ M group（0. 036 ± 0. 004 ） was significantly inhibited（ q = 11. 591, P = 0. 000 ）, and expression of Fas was lower in the Se^＋ ＋ M group than Se^- ＋ M group （0. 050 ± 0. 005 ） （ q = 7. 055, P = 0. 000）. Effect of selenium on FasL was not identified. Conclusion Increasing the intake of selenium might decrease the expression of Fas on thyroid follicular cells and restrain the development of EAT.