Download PDF
Horm Metab Res 1981; 13(8): 456-459
DOI: 10.1055/s-2007-1019300
© Georg Thieme Verlag, Stuttgart · New York

Iodine, Thyroxine (T4), Triiodothyronine (T3), 3,3′,5′-Triiodothyronine (rT3), 3,3′-Diiodothyronine (T2) in Normal Human Thyroids. Effect of Excessive Iodine Exposure

D.  Reinwein, H. A. Durrer, H. Meinhold1
  • Abteilung für Klinische Endokrinologie, Medizinische Klinik und Poliklinik der Universität Essen (GHS), Essen, Germany
  • 1Schilddrüsen-Forschungsgruppe, Nuklearmedizinische Abteilung und Endokrinologische Abteilung, Universitätsklinikum Steglitz, Freie Universität Berlin, Berlin, Germany
Further Information

Publication History

1980

1980

Publication Date:
14 March 2008 (online)

Also available at
  PDF Download  Permissions and Reprints

Summary

20 Normal glands obtained from euthyroid subjects at autopsy were analysed for total iodine (TI), PBI, L-thyroxine (T4), 3,3′,5-triiodothyronine (T3), 3,3′,5′-triiodothyronine (rT3), 3,3′-diiodothyronine (T2) after pronase hydrolysis. The mean TI was 325.1 ± 47.2 μg/g wet tissue, giving a total iodine per gland of 10.01 mg. Pretreatment of iodine containing X-ray drugs in 8 patients did not significantly affect these results with the exception of Lipiodol®. The mean T4, T3 and T2 values were 93.0 ± 23.1 μg/g, 5.25 ± 0.99 μg/g, 5.54 ± 1.05 μg/g and 0.60 ± 0.19 μg/g, respectively. In contrast to goitrous tissue, normal thyroid tissue showed no dependence of the T4/T3 ratio on the TI. Compared with goitrous tissue PBI consisted of much more T4-I in normal tissue. The corresponding values were 47.7 ± 11.8 % and 12.7 ± 3.4 %, respectively. A positive relationship was found between TI and T4, T3, rT3 but not with T2. The rT3 concentration corresponds to that of T3 in a remarkable way. The ratios of T3 to rT3 were similar, suggesting that thyroidalT3 and rT3 production is a random process. T2 represents only 0.73 % of T4-I. Our results in normal thyroid tissue clearly show that the difference in iodine concentrations is only one factor among others in comparison to goitrous tissue.

Key-Words:

Intrathyroidal Iodine Metabolism - Iodine Deficiency - Iodoamino Acids - Total Iodine - 3,3′-Diiodothyronine - Normal Thyroid Gland - Iodine Containing X-Ray Contrast Media

      >