Inhibition of rat hepatic thyroxine 5'-monodeiodinase by propylthiouracil: relation to site of interaction of thyroxine and glutathione

Journal of Endocrinological Investigation
T YamadaN Kaplowitz

Abstract

When rat liver cytosol, dialyzed free of glutathione, was chromatographed on Sephadex G-100 after incubation with 35S-propylthiouracil, 2 peaks of bound radioactivity were observed, 1 of which contained nearly all the thyroxine 5'-monodeiodinase activity in rat liver cytosol. Binding of propylthiouracil to this peak was inhibited by glutathione but not by thyroxine. Approximately 25% of 35S-propylthiouracil initially bound to the thyroxine 5'-monodeiodinating activity peak remained bound after dialysis, precipitation with trichloroacetic acid, and multipe extractions with ethanol, methanol, and chloroform, suggesting that binding was at least in part covalent. Dialysis studies showed that the presumed covalent binding of 35S-propylthiouracil to the thyroxine 5'-monodeiodinase peak could be inhibited by glutathione, dithioerythritol, and unlabelled propylthiouracil but not by oxidized glutathione or thyroxine. Conversely, thyroxine binding was unaffected by thiol compounds. We studied the kinetics of thyroxine 5'-monodeiodination by radioimmunoassay techniques using rat liver homogenates as source of enzyme and observed the dependence of enzymic reaction upon glutathione (Km = 2.4 mM). Propylthiouracil inhibited the reaction and...Continue Reading

References

Jul 15, 1977·Clinica Chimica Acta; International Journal of Clinical Chemistry·M HüfnerM Ntokalou
Feb 1, 1978·The Journal of Clinical Investigation·M M Kaplan, R D Utiger
Aug 15, 1979·Biochimica Et Biophysica Acta·T J Visser
Feb 1, 1978·Endocrinology·P ChiraseveenuprapundI N Rosenberg
Mar 10, 1975·Clinica Chimica Acta; International Journal of Clinical Chemistry·R D HeschH D Söling
Feb 1, 1975·The Journal of Clinical Investigation·M SaberiR D Utiger
Apr 1, 1976·The American Journal of Physiology·M LichterI M Arias
May 1, 1970·The Journal of Clinical Investigation·L E BravermanK Sterling
Aug 1, 1953·The Biochemical Journal·M DIXON
Mar 1, 1965·The Biochemical Journal·C W OWENS, R V BELCHER

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Citations

Nov 15, 1987·Postgraduate Medicine·Z Marshall, S Lippmann
Nov 19, 1984·FEBS Letters·E Q Colquhoun, R M Thomson
Jun 9, 2005·The Journal of Biological Chemistry·Xavier PrieurJoan C Rodríguez
Jun 14, 1984·Biochimica Et Biophysica Acta·J L Leonard, T J Visser
Apr 13, 2005·Biochemistry·James G Robertson

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