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PubMed · 2043667

Studies on the decrease of liver cytochrome P-450 content by triiodothyronine.

D L Kleiman de Pisarev·A M Ferramola de Sancovich·H A Sancovich
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Abstract

In the rat liver, the microsomal content of cytochrome P-450 decreased by 50% after triiodothyronine (T3) administration. The molecular basis for the decreased cytochrome P-450 levels was investigated. The activities of the enzymes involved in heme synthesis or degradation were not altered by thyroid hormone administration. The incorporation of 3H-delta-aminolaevulinate into the liver microsomal heme was markedly reduced in T3-treated rats. The latter appeared not to reflect a lowered binding affinity of the apoprotein moiety of cytochrome P-450 for heme. The sodium dodecyl sulfate gel electrophoresis of the microsomal preparation showed a decrease in apocytochrome P-450. It is suggested that the amount of the apocytochrome may be the primary event affected in the formation of cytochrome P-450, by triiodothyronine treatment of thyroidectomized rats.

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5-Aminolevulinate SynthetaseAminolevulinic AcidAnimalsCytochrome P-450 Enzyme SystemElectrophoresis, Polyacrylamide GelHemeHumansHydroxymethylbilane SynthaseMaleMicrosomes, LiverPorphobilinogen SynthaseProteinsRatsRats, Inbred StrainsSerum AlbuminTriiodothyronineJournal ArticleResearch Support, Non-U.S. Gov't

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D L Kleiman de Pisarev, A M Ferramola de Sancovich, H A Sancovich. 1991-05-24. Studies on the decrease of liver cytochrome P-450 content by triiodothyronine.. https://doi.org/10.1016/0304-4165(91)90057-n

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