Total T4 RIA

Product name:Total T4 RIA

Descriptions:Thyroxine (T4) is the primary active hormone synthesized within the follicular cells of the thyroid gland. T4 is synthesized via a series of steps involving: (i) iodide trapping by the follicular cells, (ii) iodination of tyrosine residues in the thyroglobulin substrate leading to formation of 3-monoiodotyrosine and 3,5-diiodotyrosine (MIT and DIT), and (iii) coupling of MIT and DIT to form either T4 or T3 (triiodothyronine). The production of T4 is approximately 3 times greater than that of T3. In plasma, ~70% of T4 is bound to thyroxine-binding globulin (TBG), 15-25% to transthyretin, 5-15% to albumin and a small percentage is bound to erythrocytes. Less than 0.1% of the total T4 circulates in a free or unbound form.