TT4 Test Kit

Thyroxine (T4), or 3,5,3',5'-tetraiodothyronine, is a thyroid hormone with a molecular weight of approximately 777Da that is released into the circulation in free form, with more than 99% bound to proteins in plasma and very small amounts of free T4 (FT4) unbound to proteins in plasma. The main functions of T4 include maintaining growth and development, promoting metabolism, producing neurological and cardiovascular effects, influencing brain development, and it is a component of the hypothalamic-pituitary-thyroid hormone regulatory system, which has a role in regulating the body's metabolism. TT4 refers to the sum of free and bound thyroxine in serum. TT4 testing is clinically used as an auxiliary diagnosis of thyroid dysfunction, and its increase is commonly seen in hyperthyroidism, subacute thyroiditis, high serum thyroxine-binding globulin (TBG), and thyroid hormone insensitivity syndrome; its decrease is seen in hypothyroidism, thyroid deficiency, chronic lymphoid Goiter, etc.