Thyroid<unk>  inhibits the enzyme thyroperoxidase, which normally acts in thyroid hormone synthesis by oxidizing the anion iodide (I−) to iodine (I0), facilitating iodine's addition to tyrosine residues on the hormone precursor thyroglobulin. This is one of the essential steps in the formation of thyroxine (T4).<unk>  does not inhibit the action of the sodium-dependent iodide transporter located on follicular cells' basolateral membranes. Inhibition of this step requires competitive inhibitors, such as perchlorate and thiocyanate. T3/T4 target tissues<unk>  also acts by inhibiting the enzyme 5'-deiodinase (tetraiodothyronine 5' deiodinase), which converts T4 to the more active form T3. (This is in contrast to methimazole, which shares<unk> 's central mechanism, but not its peripheral one.) It is important to recognize that these enzymes only work on the conjugated tyrosine molecules of T3 and T4: a completely different enzyme family is responsible for the deiodinase activity of iodized single tyrosine molecules within the thyroid follicular cells. For information on that enzyme family, see Iodotyrosine deiodinase.
Propylthiouracil
Thiamazole
Hypophysectomy
Levothyroxine
Thyroidectomy
Econazole
Cortisone acetate
Fluorouracil