THYROID HORMONE.docx

FUNCTIONAL ANATOMY. Thyroid Gland Right Lobe Trachia Largest endocrine gland 15-25 gm ================================ High blood supply - =================== HISTOLOGICAL STRUCTURE ====================== Cuboidal & contains colloid. +-----------------------------------+----------------------...

FUNCTIONAL ANATOMY. Thyroid Gland Right Lobe Trachia Largest endocrine gland 15-25 gm ================================ High blood supply - =================== HISTOLOGICAL STRUCTURE ====================== Cuboidal & contains colloid. +-----------------------------------+-----------------------------------+ | Colloid Principal cells | Parafollicular cells (C cells). | +===================================+===================================+ | Parafollicular cells | | +-----------------------------------+-----------------------------------+ Homogenous material in each THYROID HORMONES ================ T3 - 10% , Responsible for most of tissue actions. lare Calcitonin - hormone secreted by Parafollicular cells, concerned with Calcium -----------------------------------------------------------------------------    ORGANIFICATION OF THYROGLOBULINS. Iodination of tyrosine residue in thyroglobulin +-----------------------------------+-----------------------------------+ | molecule. | | +===================================+===================================+ | Tyrosine is 1 ^st^ iodinated | Iodolaelone | | | | | | Calcium other iodinated | +-----------------------------------+-----------------------------------+ | at position 3 to form | substances | | Mono-iodotyrosine | | +-----------------------------------+-----------------------------------+ | | | +-----------------------------------+-----------------------------------+ 5 to form Diiodotyrosine (DI T) -------------------------------