Part 2 Thyroid hormones and antithyroid drugs
larynx Colloid right Principal cells left thyroid -thyroid gland gland Parafollicular cells trachea Carlyn Iverson
hypothalami high low blood calcium blood calcium level thyroid a calcitonin thyroid hormone TSH bone of bone by osteoblasts contains osteoclasts b blood blood Ca2+ blood calcium level level thyroxine decreases Increases
A. Thyroid hormones
Metabolism ofthyroid hormones 1. Uptake of iodide 2. Activation of iodide(peroxidase), and iodination and coupling of tyrosine 3. Formation of thyroxine(T4) and triiodothyronine (T3)from iodotyrosine Secretion of thyroid hormones(proteolytic enzymes 5. Regulation by thyroid stimulating hormone (TSH), T4, T3
TPO g TPo g METABOLIC STEP INHIBITOR g HOI a lodide transport CIO, SCN- lumen B lodination PTU MMI EO C Coupling PTU MMI D Colloid resorption Colchicine Li2+,I- Cytochalasin B E Proteolysis 00d F Deiodination of DIT Mit Dinitrotyrosine PTU apical membrane G Deiodination of T4 cel Follicular LE MIT DIT. 5.de- iodinate 4 GT3 Follicular lumen containing Tg ECF A basement membrane - Metabolism of thyroid hormones
NH 2 ● CH.-CH-COOH L-tyrosine Ho一 CH.-CH-COOH CH.-CH-COOH monoiodotyrosine(MIT) diiodotyrosine(DIT) HO CH2-CH-COOHHO R 3,5,3-triodothyronine ( T3) Formation of NH 2 thyroxine(T,) and -CH 2-CH-COOH triiodothyronine(T3) from iodotyrosine 3, 5,3,5,tetraiodothyronine(Ta) ( thyroxine
Lumen Storage area MIT Apical cell I+Tg T Secretion of thyroid hormones( lysosomal Sydrome proteolytic enzymes) Golgi 0 0 Endoplasmic TA Nucleus Basement Bloodstream
Circadian and psychosis pulsatile rhythms Severe Cold v stress H Hypothalamus Somato Corticoids or ITRI dopamine Regulation of the AP T4,T3 secretion of thyroid hormones(feedback TSH团 inhibition) roid
Pharmacology of thyroid hormones a 1. Normalizing growth and development 2. Promoting body metabolism Body temperature; energy levels, ect. 3. Enhancing sympathetic activity
