Die Schilddrüsenhormone und thyreotropes Hormon (TSH) bei Leber- und Niereninsuffizienz

Zusammenfassung

Bei 22 Patienten mit Leber- oder Niereninsuffizienz wurden die T3- und T4-Konzentrationen im Serum, der Thyreobindungsindex und die basalen TSH-Spie-gel bestimmt. Es zeigte sich, daß der Mittelwert der T3-Konzentration bei den Leberkoma-Patienten signifikant niedriger war als bei Euthyreoten. Nieren-insuffiziente wiesen hingegen im Normbereich liegende T3-Spiegel auf, die wohl Dialyse-bedingt niedriger als bei dem Euthyreose-Kollektiv lagen. Diese Ergebnisse stehen im Einklang mit unserer früheren Feststellung, daß arterio-venöse T3-Diffe-renzen nur an der Leber, nicht jedoch an der Niere nachweisbar sind. Sie bestätigen die Annahme, daß die periphere T4/T3-Konversion im wesentlichen nur in der Leber erfolgen dürfte.

In 22 patients with hepatic or renal insufficiency the serum concentrations of trijodothyronin, thyroxine and thyrotropin and also the T4-binding capacity of TBG were determined. The mean serum T3 concentration was found to be significantly lower in patients with hepatic coma when compared with euthyroid subjects. In the cases of renal insufficiency the serum T3 concentrations were in the normal range. Due to hormone loss through dialysis however, the mean value of the T3 concentrations was slightly lower than the average concentration of normal subjects. The obtained results agree with those of our earlier studies which showed that there are significant differences between liver artery and vein T3 concentrations in serum, whereas no such differences could be ascertained between serum concentrations in renal artery and vein. On the basis of these findings it is assumed that conversion of T4 into T3 occurs predominantly in the liver.

• Literatur

• 1 Albright E. C, Larson F. C, Tust R. H. In vitro conversion of thyroxine to triiodothyronin by kidneyslices. Proc. Soc. exp. Biol. (N.Y.) 1954; 86: 137.
• 2 Albright E. C, Larson F. C. Metabolism of L-thyroxine by human tissue slices. J. clin. Invest 1959; 38: 1899.
• 3 Biersack H. J, Raabe W, Bücheler E, Winkler C. Extrathyreoidale Konversion von Thyroxin in Trijodothyronin. Nuc. Compact 1974; 5: 112.
• 4 Braverman L. E, Ingbar S. H, Sterling K. Conversion of T4 to T3 in athyreotic human subjects. J. clin. Invest 1970; 49: 855.
• 5 Carter J.N, Eastman C.J, Corcoran J. M, Lazarus L. Effect of severe, chronic illness on thyroid function. Lancet 1974; II: 971.
• 6 Chopra I. J, Solomon D. H, Chopra U, Young R. T, Teco G. N. C. Alterations in circulating thyroid hormons and thyrotropin in hepatic cirrhosis: Evidence for euthyroidism despite subnormal serum triiodothyronine. J. Endocr. clin 1974; 39: 501.
• 7 Hesch R. D, Brunner G, Söling H. D. The conversion of T4 to T3 and the subcellular localisation of the converting enzyme. Endocr. exp 8: 212 1974;
• 8 Larson P. R. Triiodothyronine: Review of recent studies of its physiology and pathophysiology in man. Metabolism 1972; 21: 1073.
• 9 Lassiter W. E, Stanbury J. B. The in vivo conversion of thyroxine to 3-5-3′triiodothyronine. J. clin. Endocr 1958; 18: 903.
• 10 Pitt-Rivers R, Stanbury J. B, Rapp B. Conversion of thyroxine to 3-5-3‘-triiodothyronine in vivo. J. clin. Endocr 1955; 15: 616.
• 11 Rabinowitz H, Hercker E. S. Thyroxine: Conversion to triiodothyronine by isolated perfused rat heart. Science 1971; 173: 1242.
• 12 Sterling K, Brenner M. A, Newman E. S. Conversion of thyroxine to triiodothyronine in normal human subjects. Science 1970; 169: 1099.
• 13 Trey C, Davidson C. S. The management of fulminant hepatic failure, in: Popper and Schaffner: Progress in liver diseases, Vol 3. Grune/Stratton/NewYork/London: 1970: 282.
• 14 Zaninovich A. A. In vitro studies on the deiodination of T4 and T3 in the rat. Acta endocr. (Kph.) Suppl 1973; 177: 154.