摘要
目的观察短期碘摄入量异常对大鼠甲状腺滤泡上皮细胞凋亡及凋亡相关基因Bcl-2、Bax蛋白水平的表达及其在不同时间段不同性别中的表达差异。方法 90只Wistar大鼠随机分为低碘组、正常组和高碘组,雌雄各半,通过饮食饮水控制使各组碘摄入量分别为0.6μg/d、6.15μg/d和61.5μg/d。分别在饲养7、14和28 d后,处死动物并分离甲状腺。HE染色,光镜下进行形态学观察;免疫组化染色,MIAS-2000型图像分析系统观察分析甲状腺细胞凋亡相关基因Bcl-2、Bax蛋白水平的表达。结果各时间段各组大鼠甲状腺滤泡上皮细胞均未检出细胞凋亡。Bcl-2、Bax在低碘组和正常组均为阴性表达,在高碘组的表达高于正常组,且有随时间延长而有增强的趋势,其中,14 d时Bax表达出现阳性;28 d时Bcl-2、Bax表达均为阳性且高于正常组(P均<0.01)。7、14 d时,高碘组Bax在两性别中均有表达,表达水平在两性别中无统计学差别;28 d时,高碘组Bcl-2、Bax表达水平雄性均高于雌性,且差别均有统计学意义(P均<0.01)。结论短期碘缺乏和碘过量均不引起细胞凋亡,短期碘缺乏对凋亡相关基因无明显影响,短期碘过量既可促进促凋亡基因表达亦可促进抑凋亡基因表达。性别因素对甲状腺细胞凋亡相关基因的表达存在一定的影响。
Objective To observe the effects of short-term iodine deficiency and excess intake on apoptosis and apoptosis-related genes expression（Bcl-2,and Bax） in the thyroid follicular epithelium cells of rats of different sexes and at different times.Methods 90 Wistar rats were randomly divided into low iodine group,normal iodine group and high iodine group,each containing two equal male and female subgroups.By controlling iodine content in the food and drinking water,the total iodine intake of each group were 0.6 μg,6.15 μg,and 61.5 μg daily,respectively.After 7,14,and 28 days,the rats were sacrificed and thyroid glands were removed.The thyroids were fixed in paraformaldehyde and stained with HE and immunohistochemistry,and observed under light microscope for morphological changes and expression of the apoptosis-related proteins.MIAS-2000 image analysis system was used to measure the percentage of positive area of thyroid follicular epithelium cells expressing Bcl-2 and Bax proteins.Results Apoptosis was not detected in follicular epithelium cells in the thyroids of male and female rats at different times.In the low iodine group and normal iodine group,the expression of apoptosis-related gene proteins was negative.The expression in the high iodine group was higher than that in the normal iodine group at different levels,and it increased with time prolonging.That is,on the 14th day,Bax appeared positive expression;and on the 28th day,Bcl-2 and Bax expressions were positive and higher than that in the normal iodine group（P0.01）.On the 7th and 14th days,Bax was expressed in both male and female rats with no significant differences,and on the 28th day,the expression of apoptosis-related genes in the male rats were higher than that in the female rats with a significant difference（P 0.01）.Conclusion Short-term iodine deficiency and excess intake does not cause apoptosis of thyroid and does not change the expression of apoptosis-related genes significantly.But short-term iodine excess intake may result in increase the expression of pro-apoptosis and anti-apotosis genes with the extension of treatment period.Effects of sex difference on the expression of apoptosis-related genes are observed in thyroid cells to a certain extent.
出处
《中国体视学与图像分析》
2011年第3期323-328,共6页
Chinese Journal of Stereology and Image Analysis
基金
天津医科大学大学生创新基金资助
