Horm Metab Res 1987; 19(8): 382-385
DOI: 10.1055/s-2007-1011830
Clinical

© Georg Thieme Verlag, Stuttgart · New York

Increased Thyrotropin Binding in Hyperfunctioning Thyroid Nodules

H.-W. Müller-Gärtner1 , C. Schneider1 , V. Bay2 , A. Tadt1 , W. Rehpenning3 , K. de Heer4 , M. Jessel1
  • 1Nuklearmedizinische Abteilung, Radiologische Klinik, Universität Hamburg, Hamburg, Germany
  • 2Chirurgische Abteilung, Allgemeines Krankenhaus Hamburg-Harburg, Hamburg, Germany
  • 3Abteilung für Mathematik und Datenverarbeitung in Medizin, Universität Hamburg, Hamburg, Germany
  • 4Abteilung für Allgemein-Chirurgie, Chirurgische Klinik, Universität Hamburg, Hamburg, Germany
Further Information

Publication History

1986

1986

Publication Date:
14 March 2008 (online)

Summary

The object of this study was to investigate TSH receptors in hyperfunctioning thyroid nodules (HFN). In HFN, obtained from seven patients, 125-I-TSH binding as determined by equilibrium binding analysis on particulate membrane preparations, was found to be significantly increased as compared with normal thyroid tissues (five patients; P < 0.001). Scatchard analysis of TSH-binding revealed two kinds of binding sites for both normal thyroid tissue and HFN, and displayed significantly increased association constants of high- and low-affinity binding sites in HFN (Ka = 11.75±6.8 109 M-1, P < 0.001 and Ka = 2.1±1.0 107M-1, P < 0.025; x ± SEM) as compared with normal thyroid tissue (Ka = 0.25±0.06 109M-1, Ka = 0.14±0.03 107M-1; x ± SEM). The capacity of the high-affinity binding sites in HFN was found to be decreased (1.8±1.1 pmol/mg protein, x ± SEM) in comparison with normal thyroid tissue (4.26±1.27 pmol/mg protein; x ± SEM). TSH-receptor autoradiography applied to cryostatic tissue sections confirmed increased TSH binding of the follicular epithelium in HFN.

These data suggest that an increased affinity of TSH-receptor sites in HFN in iodine deficient areas may be an important event in thyroid autonomy.