Stress is associated with inhibition of type I iodothyronine 5'-deiodinase activity in rat liver

Ann N Y Acad Sci. 2004 Jun;1018:219-23. doi: 10.1196/annals.1296.026.


Type I iodothyronine deiodinase (5'-DI) generates the thyromimetically active hormone 3,5,3'-triiodothyronine (T(3)) by reductive monodeiodination of the phenolic ring of L-thyroxine (T(4)). The present study was undertaken to compare the effects of cold stress (4 degrees C) alone or in combination with immobilization stress (IMO), insulin treatment (5 IU/kg, i.p.) or 2-deoxy-D-glucose (2DG)-induced intracellular glucopenia on the activity of 5'-DI in rat liver. Cold stress either for 24 h or 28 days when compared to that in the nonstressed group of rats significantly reduced (P < 0.001) the activity of 5'-DI in liver. In comparison with cold stressed rats for 28 days, an additional decrease in 5'-DI activity was observed when those rats underwent 1 x IMO in cold for 2 h (P < 0.001) or insulin treatment (P < 0.05). A significant decrease in 5'-DI activity was found also in rats maintained at room temperature that underwent a single 1 x IMO for 2 h (P < 0.001) or insulin treatment (P < 0.01) when compared to nonstressed animals. In comparison with nonstressed rats, no significant change of the 5'-DI activity was observed after 2DG application (500 mg/kg, i.p.) at room temperature. In conclusion, cold stress and/or 1 x IMO, insulin treatment, or 1 x IMO at room temperature markedly affects reductive monodeiodination of T(4), and thus reduces the concentration of biologically active T(3) in liver.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Deoxyglucose / pharmacology
  • Immobilization
  • Iodide Peroxidase / antagonists & inhibitors*
  • Liver / enzymology*
  • Male
  • Rats
  • Rats, Sprague-Dawley
  • Stress, Physiological / enzymology*


  • Deoxyglucose
  • Iodide Peroxidase