triiodothyronine

References

triiodothyronine

hormone

Also known as: 3,5,3′-triiodothyronine, L-triiodothyronine, T3(Show More)

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July 14, 2026

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Triiodothyronine, also known as T3, is an iodine-containing hormone derived from thyroxine. It is one of the two primary hormones secreted by the thyroid gland, with the other being thyroxine (T4). The thyroid gland, located in the neck, produces these hormones which are vital for metabolism and growth.1234

Thyroxine contains four iodine atoms, while triiodothyronine contains three. Although the thyroid gland produces more thyroxine, it is converted into triiodothyronine in many tissues, and it is primarily triiodothyronine that exerts the action of thyroid hormone in the body's target tissues. This hormone plays a crucial role in stimulating oxygen consumption and regulating metabolism across all body cells and tissues.214

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therapeutics
Hormones
hormones include thyroxine and triiodothyronine, which regulate tissue metabolism. Natural desiccated thyroid produced from beef and pork and the synthetic derivatives levothyroxine and liothyronine are used in replacement therapy to treat hypothyroidism that results from any cause.
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hormones include thyroxine and triiodothyronine, which regulate tissue metabolism. Natural desiccated thyroid produced from beef and pork and the synthetic derivatives levothyroxine and liothyronine are used in replacement therapy to treat hypothyroidism that results from any cause.
Read More

hyperthyroidism
Diagnosis of hyperthyroidism
two thyroid hormones, thyroxine and triiodothyronine, with the former being produced in much greater quantities than the latter. Thyroid hormones exist in two forms, one of which is bound to several proteins, and the other of which, a very small amount, is free. Thus, serum thyroxine can be measured as…
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two thyroid hormones, thyroxine and triiodothyronine, with the former being produced in much greater quantities than the latter. Thyroid hormones exist in two forms, one of which is bound to several proteins, and the other of which, a very small amount, is free. Thus, serum thyroxine can be measured as…
Read More

human endocrine system
Feedback regulation mechanisms of endocrine signaling
… (T₄) may be converted to triiodothyronine (T₃), a change that substantially increases its hormonal potency, or it may be converted to reverse triiodothyronine (reverse T₃), a molecule with the same three iodine atoms that has minimal biological activity.
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… (T₄) may be converted to triiodothyronine (T₃), a change that substantially increases its hormonal potency, or it may be converted to reverse triiodothyronine (reverse T₃), a molecule with the same three iodine atoms that has minimal biological activity.
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