These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Reciprocal changes in serum 3, 3', 5'-tri-iodothyronine concentration and the peripheral thyroxine inner ring monodeiodination during food restriction in the young pig.
    Author: Slebodziński AB, Brzezińska-Slebodzińska E, Drews R.
    Journal: J Endocrinol; 1982 Dec; 95(3):349-55. PubMed ID: 7175423.
    Abstract:
    Utilizing the difference in pH optima between two distinct enzyme systems responsible for the thyroxine (T4) inner and outer ring monodeiodination, and a specific radioimmunoassay for iodothyronines, the net T4 conversion to 3, 3', 5'-tri-iodothyronine (rT3) and 3, 5', 3'-tri-iodothyronine (T3) in growing pigs kept under various food restrictions was determined in vitro. It has been found that fasting lowers deiodination of T4 to T3 by liver and kidney homogenates. The conversion of T4 to rT3 was reduced in the liver but not in the kidney, unless the animals were completely fasted. During food restriction serum T4 and T3 decreased whereas rT3 increased, which indicated that the serum rT3 level is not a good reflection of T4 to rT3 converting activity in the liver or kidney. The data suggest that a rise in rT3 reflects a lowered degradation rate of the hormone or an increased secretion by the thyroid gland rather than changes in rT3 neogenesis in the periphery.
    [Abstract] [Full Text] [Related] [New Search]