Savoie J C, Massin J P, Savoie F
J Clin Invest. 1973 Jan;52(1):116-25. doi: 10.1172/JCI107154.
Butanol-insoluble iodinated compounds in the urine of patients with congenital goiters have been generally regarded as iodopeptides. Monoiodohistidine (MIH) and diiodohistidine (DIH) were identified from the urine of four patients with congenital goitrous hypothyroidism. From radioiodine studies, 40-70% of the urinary radioactivity was in the iodide-free fraction from which about 40% was identified as MIH and DIH by crystallizations to a constant specific activity. Iodotyrosines were simultaneously identified in the urine. However the presence of an iodotyrosine-deiodinase activity was demonstrated in the two removed goiters with a normal K(m) for MIT. In vivo iodotyrosine deiodination was normal for hypothyroid subjects. No thyroglobulin was identified in the thyroids from these patients. The major iodoprotein was iodoalbumin which, after in vivo labeling, contained 84-89% of the total soluble protein radioactivity. The thyroxine content of the goiter iodoalbumins and other iodoproteins was extremely low. Iodohistidines were identified in comparable proportions in the iodoalbumin and in the other iodoproteins isolated from each goiter. The average iodohistidine content of these proteins as crystallizable MIH and DIH was in the individual cases 15 and 4% of the in vivo incorporated radioiodine. DIH was identified in all iodoprotein fractions. The mean DIH/MIH ratios from the individual cases were 1.16 and 0.35. The corresponding DIT/MIT ratios were 3.19 and 1.45, respectively. The major consequence of this thyroglobulin defect is the iodination of inappropriate proteins (mainly albumin) resulting in low yields of thyroxine and high yields of iodohistidines. Iodohistidines from the goiter iodoproteins were not deiodinated and, at least for MIH, were quantitatively excreted in the urine of these patients. From the MIH iodoalbumin content and the MIH urinary excretion, goiter iodoalbumin turnover estimates were made and, although elevated, could not maintain a normal thyroxine secretion. The urinary excretion of iodohistidines easily demonstrated by column chromatography is offered as a test for detecting this variety of congenital goiter.
先天性甲状腺肿患者尿液中不溶于丁醇的碘化化合物通常被视为碘肽。从4例先天性甲状腺肿性甲状腺功能减退患者的尿液中鉴定出了一碘组氨酸（MIH）和二碘组氨酸（DIH）。通过放射性碘研究发现，尿液中40%-70%的放射性存在于无碘化物部分，通过结晶至恒定比活度，其中约40%被鉴定为MIH和DIH。同时在尿液中鉴定出了碘酪氨酸。然而，在两个切除的甲状腺肿中证实存在碘酪氨酸脱碘酶活性，其对MIT的K(m)正常。甲状腺功能减退患者的体内碘酪氨酸脱碘正常。在这些患者的甲状腺中未鉴定出甲状腺球蛋白。主要的碘蛋白是碘白蛋白，在体内标记后，其包含总可溶性蛋白放射性的84%-89%。甲状腺肿碘白蛋白和其他碘蛋白中的甲状腺素含量极低。在从每个甲状腺肿分离出的碘白蛋白和其他碘蛋白中，碘组氨酸的比例相当。这些蛋白质中可结晶的MIH和DIH形式的平均碘组氨酸含量在个别病例中分别为体内掺入放射性碘的15%和4%。在所有碘蛋白组分中均鉴定出了DIH。个别病例的平均DIH/MIH比值分别为1.16和0.35。相应的DIT/MIT比值分别为3.19和1.45。这种甲状腺球蛋白缺陷的主要后果是不适当蛋白质（主要是白蛋白）的碘化，导致甲状腺素产量低而碘组氨酸产量高。甲状腺肿碘蛋白中的碘组氨酸不会脱碘，至少对于MIH而言，会定量排泄到这些患者的尿液中。根据MIH碘白蛋白含量和MIH尿排泄量对甲状腺肿碘白蛋白周转率进行了估算，尽管周转率升高，但仍无法维持正常的甲状腺素分泌。通过柱色谱法很容易证明的碘组氨酸尿排泄可作为检测这种先天性甲状腺肿的一项检测方法。
