中文摘要：

目的 观察碘对牛甲状腺球蛋白（bTg）诱导的实验性自身免疫性甲状腺炎（EAT）大鼠血清趋化因子IP-10及甲状腺组织IP-10 mRNA表达的影响.方法 选择4周龄雌性Lewis大鼠135只,采用随机数字表法按体质量分为对照组（NC,20只）、模型组（TG,25只）、高碘Ⅰ组（HⅠ,20只）、高碘模型Ⅰ组（HⅠ ＋TG,25只）、高碘Ⅱ组（HⅡ,20只）和高碘模型Ⅱ组（HⅡ＋ TG,25只）.HⅠ、HⅠ ＋TG组大鼠饮用含碘25.7 μg/L的去离子水,HⅡ、HⅡ＋ TG组大鼠饮用含碘423.3 μg/L的去离子水,NC、rG组饮用蒸馏水.TG、HⅠ ＋TG和HⅡ＋TG组大鼠皮下注射含8g/L bTg的不完全弗氏佐剂0.1 ml,每2周1次,共3次.15周末处死动物,采用砷-铈催化分光光度法（WS/T 107-2006）测定大鼠尿碘,光镜下观察甲状腺组织病理学改变,酶联免疫吸附试验（ELISA）检测大鼠血清IP-10含量,实时荧光定量PCR法检测甲状腺IP-10 mRNA表达.结果 各组大鼠尿碘中位数比较差异有统计学意义（x2=106.4,P＜0.05）.其中TG、HⅠ、HⅠ ＋TG、HⅡ、HⅡ ＋TG组大鼠尿碘中位数（800.08、18 633.20、13 869.08、87 889.97、61 661.51 μg/L）均高于NC组（456.45 μg/L,P均＜0.05）.各组大鼠病理改变等级随着碘摄入的提高逐渐加重,其中NC组大鼠甲状腺结构正常;TG组大鼠甲状腺滤泡间少量淋巴细胞浸润;HⅠ组大鼠甲状腺滤泡排列不整齐、部分滤泡组织破坏;HⅡ组大鼠甲状腺滤泡间大量炎性细胞浸润;HⅡ＋ TG组大鼠甲状腺滤泡严重破坏、炎细胞弥漫性浸润.6组大鼠血清IP-10含量比较,差异无统计学意义（F=1.462,P＞ 0.05）.HⅠ ＋TG组大鼠甲状腺IP-10 mRNA表达（2.80±1.73）高于NC组（1.65±1.62）和HⅠ组（1.07±1.00）,HⅡ（0.64±0.64）、HⅡ ＋TG组（0.80±0.49）低于HⅠ ＋TG组（P均＜0.05）.结论 过量碘摄入可增加EAT大鼠甲状腺组织中炎性程度,加重病理改变;这可能与过量碘影响甲状腺IP-10 mRNA表达有?

英文摘要：

Objective To establish experimental autoimmune thyroiditis （EAT） rat model induced by bovine thyroglobulin （bTg） and to observe the effect of iodine on IP-10 in rat serum and IP-10 mRNA expression in rat thyroid tissue.Methods One hundred and thirty-five four-week old female Lewis rats were divided into normal control （NC,20 rats） group;TG group,25 rats;H Ⅰ group,20 rats;H Ⅰ ＋ TG group,25 rats;H Ⅱ group,20 rats and H Ⅱ ＋ TG group,25 rats according to a random number table.The water iodine concentration was 25.7 μg/L given to rats of HⅠ and H I ＋ TG groups,and 423.3 μg/L of H Ⅱ and H Ⅱ ＋ TG groups.Rats of NC and TG groups drank distilled water.Rats of TG,H Ⅰ ＋ TG,H Ⅱ ＋ TG groups were immunized with 0.1 ml bTg （8 g/L） in IFA.All rats were killed at the end of 15 weeks.Urinary iodine was determined by As3＋-Ce4＋ catalytic spectrophotometry （WS/T 107-2006）.Pathological changes in thyroid tissue were observed by light microscope.Serum IP-10 was determined by enzyme-linked immunosorbent assay （ELISA）,and IP-10 mRNA expression in thyroid was detected by real-time PCR.Results The differences of urinary iodine between groups were statistically significant （x2 =106.4,P 〈 0.05）.Compared with NC group （456.45 μg/L） urinary iodine in other groups increased significantly （TG,H Ⅰ,H Ⅰ ＋ TG,HⅡ,HⅡ ＋ TG：800.08,18 633.20,13 869.08,87 889.97,61 661.51 μg/L,all P 〈 0.05）.The pathological changes of rats in each group aggravated following increased iodine intake,NC group had normal thyroid structure;thyroid of TG group had a small amount of lymphocytes;thyroid of H Ⅰ group showed irregular follicular,part of the follicular was destroyed;a large number of lymphocytes infiltrated between follicular of H Ⅱ group;in H Ⅱ ＋ TG group,the follicular was destroyed severely,diffuse inflammatory cell infiltration.The difference of serum IP-10 between groups no were statistically significant （F =1.462,P 〉 0.05）.The expression of IP-10 mRNA of H