QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Hastings, M. M. Articles by Zeman, F. J. Search for Related Content PubMed PubMed Citation Articles by Hastings, M. M. Articles by Zeman, F. J.

Production and Metabolism of Thyroid Hormones in Protein-Deficient and Food-Restricted Pregnant Rats^{1, 2,}

Department of Nutrition, University of California, Davis, California 95616

Thyroxine (T₄) and triiodothyronine (T₃) concentrations in the plasma and their metabolic clearance and production rates were studied in pregnant protein-deficient and food-restricted rats on the 20th day of gestation. Total T₃ levels in the plasma were significantly reduced in malnourished dams, with those of food-restricted dams being consistently lower than those of protein-deficient dams. There were no changes in plasma total T₄ concentrations as a result of dietary treatment. Unbound T₄ and T₃ in the plasma were significantly reduced in both protein-deficient and food-restricted dams. Maternal protein deficiency significantly lowered fetal T₄, whereas food restriction caused an elevation. Metabolic clearance rates of T₃ and T₄ and production rate of T₄ were unaffected by diet, while the production rate of T₃ was significantly increased in protein deficient dams. Thyroxine to triiodothyronine ratios in malnourished dams were elevated suggesting depressed peripheral conversion of T₄ to T₃. Alternative factors which may lead to these effects are discussed.

KEY WORDS: • protein deficiency • thyroxine • triiodothyronine • pregnancy

¹ Supported in part by Public Health Service Grant No. HD-08499 from the National Institute of Child Health and Human Development.

² Presented in part at the 1978 meeting of the Federation of American Societies for Experimental Biology, Atlantic City, New Jersey, April 9–14, 1978. Federation Proc. 37, 332 (Abstr.).

³ Present address: The Procter and Gamble Co., Miami Valley Laboratories, P.O. Box 39175. Cincinnati, Ohio 45247.

⁴ To whom reprint requests should be sent.

Manuscript received 9 March 1979.