【摘要】 1.大鼠接受示踪量的放射性碘后,其甲状腺总蛋白的此放射性随着时间的变化与放射自显影中放射性的增减有相同的趋势。甲状腺蛋白质中的放射性基本集中在可溶性部分,而后者的纸电泳谱显示相当于甲状腺球蛋白的单一放射性峰。实验结果证明,甲状腺组织放射自显影谱中的放射性颗粒能够反映甲状腺球蛋白分子上的碘。2.在四个不同时相的甲状腺组织放射自显影谱中,放射性颗粒主要集中在腺泡的胶体部分。但在有的标本中,上皮细胞内也看到 I¹³¹的存在,并有环状影象出现。这结果支持了碘化过程在细胞内进行的观点。更多还原

【Abstract】 This paper deals with(1)the nature of the autoradiographic material of thyroid sections,based on biochemical experi- ments,and(2)the site of iodination in the thyroid gland. Thyroid proteins were isolated from rats which had received tracer doses of radioactive iodide.The radioactivity of the thyroid proteins at various time intervals after the administration of radioiodine was found to change in a manner parallel to the variation in the intensity of radioactive image in the radioautographs.Over 90 % of the radio- activity of the thyroid proteins was con- centrated in the soluble fraction,e.i.the fraction extractable with cold normal saline solution.This soluble fraction moved during paper electrophoresis as a single peak,which corresponded to that of thyroglobnlin.Since the radioactive iodine left in the thyroid section repre- sents protein-bound iodine,the results of our experiments clearly indicate that auto- radiographic image in thyroid sections does reflect the hormonal iodine or iodine present in the thyroglobulin. All thyroid autoradiographs,made several hours or more after administration of the radioiodine,showed localization of the radioactivity mainly in the colloid. However,in some of the autoradiographs, black rings overlying the follicular epi- thelial cells also appeared.These findings give support to the hypothesis that iodina- tion of the protein first takes place in the thyroid cells and the iodinated protein then rapidly diffuses into the follicle lumen.更多还原