IODINE TRANSPORT IN THE THYROID: ROLE IN DIAGNOSIS TREATMENT OF NODULAR THYROID DlSEASE CANCER

摘要

Thyroid hormone is essential for normal development, especially brain and bone. It has important actions in the adult in essentially all tissues, but is especially important in metabolic regulation. Thyroid hormone is synthesized in the thyroid glandprimarily as the prohormone, thyroxine (T4), and it is activated in tissues by the 5'-deiodinase enzymes to the active form, triiodothyronine (T3). Synthesis of thyroid hormone is regulated by thyroid stimulating hormone (TSH) secreted from the anteriorpituitary under negative feedback regulation by T4 and T3. TSH is also regulated by Thyrotropin Releasing Hormone (TRH), secreted from the hypothalamus, which is also under negative feedback regulation from T4 and T3.