Quick Facts
- Also called:
- 3,5,3′,5′-tetraiodothyronine, or T4
- Related Topics:
- thyroid gland
- aryl halide
- thyroid hormone
- On the Web:
- National Center for Biotechnology Information - Thyroxine Poisoning (Nov. 02, 2026)
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Thyroxine
hormone
Also known as: 3,5,3′,5′-tetraiodothyronine, L-tetraiodothyronine, L-thyroxine, T4(Show More)
Thyroxine, one of the two major hormones secreted by the thyroid gland (the other is triiodothyronine). Thyroxine’s principal function is to stimulate the consumption of oxygen and thus the metabolism of all cells and tissues in the body. Thyroxine is formed by the molecular addition of iodine to the amino acid tyrosine while the latter is bound to the protein thyroglobulin. Excessive secretion of thyroxine in the body is known as hyperthyroidism, and the deficient secretion of it is called hypothyroidism. The chemical structure of thyroxine is
This article was most recently revised and updated by Erik Gregersen.
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