Journal of Clinical Endocrinology & Metabolism, Vol 78, 1505-1509, Copyright © 1994 by Endocrine Society

ARTICLES

A 3,3'-diiodothyronine sulfate cross-reactive compound in serum from pregnant women

SY Wu, DH Polk, WL Chen, DA Fisher, WS Huang and B Yee
Department of Nuclear Medicine and Medicine, Veterans Administration- University of California-Irvine Medical Center, Long Beach 90822.

Recently, we found high serum/urine concentrations of 3,3'- diiodothyronine sulfate (T2S) in both fetal and maternal sheep. In the present study, a RIA was employed to detect and measure serum T2S in women of different gestational ages and after delivery. Results were compared with values in nonpregnant women. In maternal serum, we identified a material that cross-reacts with T2S antibody, but is not T2S. Its concentration increased with the progression of pregnancy. The exact chemical structure of the T2S-like material (which we designated compound W) is unclear. It is immunologically (or chemically) similar to T2S, but does not cochromatograph with synthetic T2S in high pressure liquid chromatography. The serum concentrations of compound W were expressed as T2S equivalents (nanomoles per L +/- SE). Serum compound W concentrations were slightly elevated in women during the first trimester compared to those in nonpregnant women (0.73 +/- 0.04 vs. 0.17 +/- 0.02 nmol/L; P < 0.01). There was a moderate and progressive rise in the compound W concentration between 14-35 weeks gestation. The maternal serum compound W concentration then rapidly peaked before parturition (36-40 weeks gestation, 3.49 +/- 0.49 nmol/L; 27-35 weeks, 1.67 +/- 0.11 nmol/L; P < 0.01). After parturition, maternal serum levels of compound W decreased from 2.61 +/- 0.18 nmol/L (n = 25) to 1.47 +/- 0.12 nmol/L (n = 18) at 1 day, 0.89 +/- 0.07 nmol/L (n = 15) at 3 days, and 0.33 +/- 0.03 nmol/L (n = 8) at 7 days. hCG increased serum concentrations of T2S-cross-reactive material 6.2- fold (P < 0.01) in nonpregnant women. In summary, whereas hCG stimulation may account for some increase in maternal serum concentrations of this T2S-like material in the first trimester, the more rapid increase in maternal serum compound W concentrations during the late third trimester are probably related to changes that occur in fetal thyroid hormone economy. It is speculated that placental transfer and transformation of fetal T3 may be related to the rise in the level of T2S-like compound W in the serum of pregnant women.

This article has been cited by other articles:

				G. Pinna, O. Brodel, T. Visser, A. Jeitner, H. Grau, M. Eravci, H. Meinhold, and A. Baumgartner Concentrations of Seven Iodothyronine Metabolites in Brain Regions and the Liver of the Adult Rat Endocrinology, May 1, 2002; 143(5): 1789 - 1800. [Abstract] [Full Text] [PDF]

				S.-Y. Wu, D. H. Polk, W.-S. Huang, and D. A. Fisher Fetal-to-maternal transfer of 3,3',5-triiodothyronine sulfate and its metabolite in sheep Am J Physiol Endocrinol Metab, November 1, 1999; 277(5): E915 - E919. [Abstract] [Full Text] [PDF]

				M. H. A. Kester, E. Kaptein, T. J. Roest, C. H. van Dijk, D. Tibboel, W. Meinl, H. Glatt, M. W. H. Coughtrie, and T. J. Visser Characterization of Human Iodothyronine Sulfotransferases J. Clin. Endocrinol. Metab., April 1, 1999; 84(4): 1357 - 1364. [Abstract] [Full Text]

				K. Richard, R. Hume, E. Kaptein, J. P. Sanders, H. van Toor, W. W. de Herder, J. C. den Hollander, E. P. Krenning, and T. J. Visser Ontogeny of Iodothyronine Deiodinases in Human Liver J. Clin. Endocrinol. Metab., August 1, 1998; 83(8): 2868 - 2874. [Abstract] [Full Text]