The thyroid gland is an endocrine organ that secretes the hormones triiodothyronine (T3) and thyroxine (T4), which are, in turn, under the influence of the TSH and the TRH. Though hyperand hypothyroidism remain the common clinically manifesting condition of the thyroid, in some cases, the patient remains symptomless with either excess or decrease in thyroxine levels, along with normal TSH level...

The thyroid gland is an endocrine organ that secretes the hormones triiodothyronine (T3) and thyroxine (T4), which are, in turn, under the influence of the TSH and the TRH. Though hyperand hypothyroidism remain the common clinically manifesting condition of the thyroid, in some cases, the patient remains symptomless with either excess or decrease in thyroxine levels, along with normal TSH level...

The thyroid gland is an endocrine organ that secretes the hormones triiodothyronine (T3) and thyroxine (T4), which are, in turn, under the influence of the TSH and the TRH. Though hyperand hypothyroidism remain the common clinically manifesting condition of the thyroid, in some cases, the patient remains symptomless with either excess or decrease in thyroxine levels, along with normal TSH level...

Cellular and nuclear uptake of [125I]tri-iodothyronine (T3) and [125I]triiodothyroacetic acid (Triac) were compared in cardiomyocytes of 2-3 day old rats, and the effect of thyroid hormone analogs on cellular T(3) uptake was measured. Cells (5-10 x 10(5) per well) were cultured in DMEM-M199 with 5% horse serum and 5% FCS. Incubations were performed for from 15 min to 24 h at 37 degrees C in the...

Tissue specificities in inhibitory action of excess triiodothyronine (T3) on creatine uptake from the plasma and the effect of denervation of the muscle on the inhibitory action were studied in rats with the use of radioactive creatine. The uptake of radioactive creatine of all muscles studied significantly diminished after T3 (100 microgram/100 g, s.c.) injection, while that of brain was not a...

The action of L-triiodothyronine (T3) on amino acid transport in the GC clonal strain of rat pituitary cells was investigated by measurement of the uptake of the nonmetabolizable amino acid, alpha-aminoisobutyric acid (AIB). The uptake of AIB by GC cells appeared to require energy and Na+ and displayed Michaelis-Menten kinetics. In comparison to cultures maintained in the absence of T3, T3 addi...

The uptake and efflux of reverse triiodothyronine (rT3) in JAr cells were investigated. Uptake of 125I-rT3 was time dependent and reversible with a saturable component of around 70 per cent of total uptake after 30 min of incubation. Efflux was not saturable. Kinetic analysis of the initial specific uptake rates revealed an uptake process with a Michaelis constant of 3.04+/-0.53 microM (mean+/-...

A triiodothyronine uptake test in which antibody-coated tubes are used (Clinical Assays) was compared to two other such tests in which silicate tablets (Nuclear-Medical Laboratories, Inc.) or macroaggregated albumin (Diagnostic Corporation of America) are used to separate the bound from the free fraction. The Clinical Assays test showed good linear correlation with the values obtained by the ot...

The present experiments were designed to explore the mechanism whereby 3,5,3'-triiodothyronine (T3) stimulates the uptake of 2-deoxy-D-glucose (2-DG) in rat thymocytes in vitro. Addition of T3 evoked a transient, dose-related increase in cellular cyclic (c) AMP concentrations, evident within 5 min. followed soon by an increase in 2-DG uptake. The effects of T3 on both cAMP concentration and 2-D...