【作者】 林来祥； 孙毅娜； 张璐； 阎玉芹； 陈祖培；

【Author】 LIN Laixiang, SUN Yina, ZHANG Lu, YAN Yuqin, CHEN Zupei (Institute of Endocrinology, Tianjin Medical University, Tianjin 300070)

【机构】 天津医科大学内分泌研究所；

【摘要】 目的检测碘缺乏和碘过量对甲状腺细胞凋亡和增殖的影响,以期为防治碘致性甲状腺疾病提供理论依据。方法将断乳后1个月Wistar大鼠随机分为5组(即低碘组、适碘组、5倍碘组、10倍碘组、50倍碘组),各组大鼠饮用不同碘浓度的水(加入不同剂量的碘酸钾),大鼠每日总碘摄入量分别为0．6、6．15、30．75、61．5、307．5μg／d。在实验第7天、14天及28天,处死动物并分离甲状腺。采用RT- PCR检测细胞凋亡相关基因fas、fasL mRNA表达,免疫组化方法检测细胞Fas、FasL蛋白及PCNA的表达,TUNEL法检测凋亡细胞。结果与适碘组比较,各时间段低碘组大鼠甲状腺fas和fasL mRNA的表达均无明显变化,高碘组表达有随碘摄入量增加而增强的趋势。Fas和FasL蛋白在各时间段,低碘组和适碘组稳定的表达为阴性或弱阳性,高碘组阳性强度随碘摄入量和摄入时间增加而增强。在各时间段,低碘组大鼠甲状腺PCNA表达阳性细胞率均明显高于适碘组; 各高碘组无显著变化。各组大鼠各时段均未发现阳性凋亡细胞。结论短期碘缺乏未引起细胞凋亡,但促进细胞增殖;短期碘过量对甲状腺细胞凋亡和增殖活性均无影响;机体对碘过量有更强的适应能力。更多还原

【Abstract】 Objective explore the effects of iodine on thyroid apoptosis and proliferation. Method One-month weaning Wistar rats were randomly divided into five groups (low iodine-LI, normal iodine-NI, five fold high iodine-5HI, ten fold high iodine-10HI, fifty-fold high iodine-50HI) , and fed with water containing different iodine concentrion by adding potassium iodate respectively, all groups got prospective iodine intake, that is,0.6, 6. 15, 30.75, 61.5, and 307. 5 μg/d. After 7 days, 14 days, 28 days, rats were sacrificed. We also tested thyroid proliferation, apoptosis, and apoptosis related genes expression by TUNEL, immunohistochemistry and RT-PCR. Results After short-term administration, mRNA expression of fas and fasL genes showed no significant change in LI group, but trended to go up in iodine excess groups according to the increase of iodine intake. Fas and FasL proteins expressions were consistent in LI and NI groups, and all of them were negative or weak positive; in HI groups their staining density rised.with the increase of iodine intake and length of administration period. Expression of PCNA was enhanced by short-term iodine deficiency, but not by short-term iodine excess. Apoptosis was not found in all groups. Conclusion Both short-term iodine deficiency and iodine excess have no obvious effects on thyrocytes apoptosis. Proliferation can be induced by short-term iodine deficiency, but not by iodine excess. Wistar rats demonstrate strong tolerance to long-term iodine excess.更多还原