Reverse triiodothyronine (rT3) is metabolized predominantly by outer ring deiodination to 3,3'-diiodothyronine (3,3'-T2) in the liver. Metabolism of rT3 and 3,3'-T2 by isolated rat hepatocytes was analyzed by Sephadex LH-20 chromatography, high performance liquid chromatography, and radioimmunoassay, with closely agreeing results. Deiodinase activity was inhibited with propylthiouracil (PTU) an...

The aim of the present work was to investigate response zebrafish effects widely-used organophosphates roundup and chlorpyrifos putative effectiveness chlorella in terms decreasing pesticides toxicity. Studied organophosphate pesticide ecologically relevant concentrations, both individually a mixture, evoked prominent suppression catalase total antioxidant capacity liver Danio rerio which were ...

We have analyzed the effect of triiodothyronine and the tumor promoter 12-O-tetradecanoylphorbol-13-acetate on expression of the transformed phenotype, as monitored by agar clonigenicity, in a single cell clone of type 5 adenovirus-transformed Sprague-Dawley rat embryo cells, E11, and a nude mouse tumor-derived E11 subclone, E11-NMT. When grown in medium devoid of thyroid hormone, the cloning e...

triiodothyronine combination therapy versus thyroxine monotherapy for clinical hypothyroidism: meta-analysis of randomized controlled trials. J Clin Endocrinol Metab. 2006;91(7):2592-2599. 14. Appelhof BC, Brouwer JP, van Dyck R, et al. Triiodothyronine addition to paroxetine in the treatment of major depressive disorder. J Clin Endocrinol Metab. 2004;89(12):6271-6276. 15. Joffe RT, Brimacombe ...

The major clinical role for total triiodothyronine (TT3) and (or) free T3 (FT3) is the assessment of hyperthyroidism in patients with suppressed sensitive thyrotropin (sTSH) concentrations. The assays are particularly important in hyperthyroid patients with normal free thyroxine (FT4) concentrations to assess potential T3 thyrotoxicosis. Other specialized uses for T3 and FT3 measurements are mo...

We investigated whether the inhibition of placental T4 5-deiodinase (5-D) activity would decrease the amniotic fluid (AF) concentration of rT3. Iopanoic acid (TOP) was used to inhibit placental T4 5-D activity. From gestation days 14 to 17, a group of rats received IOP (10 mg/100 g bwlday, sc) once daily in experiment (exp) 1, and received it (40 mg/100 g bw/day) four times daily in exp 2. In e...

We observed that the level of reverse triiodothyronine (rT3) was significantly increased after partial hepatectomy (PH) in both wild-type and constitutively active/androstane receptor (CAR) knockout (KO) mice, and treatment with phenobarbital (PB), a CAR activator, after PH decreased rT3 to restore its original level only in wild-type mice. On the other hand, no significant changes in the level...

To clarify whether serum free fatty acid (FFA) is an inhibitor of extrathyroidal conversion (IEC) of thyroxine (T4) to thyronine (T3), we measured the concentration of FFA, IEC activity and thyroid hormones in normal subjects, acute ketotic children and children with low T3 syndrome due to nonthyroidal illness (NTI). Iodothyronine (I) 5'-deiodinase activity was assayed with reverse triiodothyro...