What factors increase conversion of T4 hormone to T3?
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Lean body mass is a significant factor influencing the peripheral conversion of thyroxine (T4) to triiodothyronine (T3) in individuals with hypothyroidism and minimal functioning thyroid tissue . Additionally, during prolonged fasting, an increased peripheral T4 to T3 conversion occurs, especially in the presence of growth hormone (GH) . Furthermore, stimulation of sympathetic nerves to interscapular brown adipose tissue (IBAT) by neostigmine injection in the hippocampus can increase T3 levels and 5'-deiodinating activity of IBAT, enhancing the conversion of T4 to T3 . These findings collectively suggest that factors such as lean body mass, GH, and sympathetic nerve stimulation can contribute to the increased conversion of T4 to T3 in various physiological conditions.
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| Factors increasing T4 to T3 conversion in Elaphe taeniura include substrate concentration, dithioerythritol, temperature, pH, and sensitivity to iopanoic acid, propylthiouracil, salicylate, and propranolol. | |
| Neostigmine injection in the hippocampus increases T4 to T3 conversion by elevating blood T3 levels and stimulating sympathetic nerves to interscapular brown adipose tissue. | |
9 Citations | Growth hormone (GH) and prolonged fasting stimulate the conversion of thyroxine (T4) to triiodothyronine (T3) in dwarf goats, indicating GH's role in enhancing this conversion during food deprivation. |
1 Citations | Increased conversion of T4 to T3 is influenced by autonomously functioning thyroid adenoma (AFTA) tissue, leading to elevated serum T3 levels and suppressed TSH, especially in evolving hyperthyroidism. |
| Lean body mass is a significant factor that increases the conversion of T4 to T3 hormone in athyreotic individuals during levothyroxine replacement therapy. |
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