pituitary-thyroid hormone productionafter birth8++a品3&R#0PATERT3TSH....TSH2Fo120Hormones in fetalHormones after birth(Hour)Within30 minutes of delivery, TSHabrupt rise occurs --as a protected results ofchange inenvironmental temperature.TSHlevels: first 12h as high as 70um/ml; after 48h:<20; after 120h:<5 T4and T3: TSHsurge causes marked increase in T4,T3 by 24h to 48h
pituitary-thyroid hormone production after birth Hormones in fetal Hormones after birth(Hour) Within 30 minutes of delivery, TSH abrupt rise occurs -as a protected results of change in environmental temperature. TSH levels: first 12h as high as 70um/ml; after 48h:<20; after 120h:<5 T4 and T3: TSH surge causes marked increase in T4,T3 by 24h to 48h
Synthesis of Thyroid HormoneDietary iodide (latomicwt.127)A.RapidabsorptionlodideCouplingTrappingFOLLICULARKCELLSATP-50mV一Colloid dropletsTSHbypinocytesisCOLLOIDElectrochemicalTSHMTMITgradientPeroxidaseATP B.lodide trapF.Lysosomal peptidasesTGDIT人TTNaTGHydrolyzeT/T.GMITandDITDC.EndoplasmicreticulumDeiodinase.Thyroglobulir to Golgi complexVesiclesOrganification/OxidationFig.28-1KMCH.TsHstimulatesthyroid homonesynthesisandsecretion
Coupling Organification/ Oxidation Iodide Trapping Synthesis of Thyroid Hormone TSH TSH Hydrolyze
Regulation of thyroid hormonesecretionEhoreptoraCTRrOnstlamninergicCRHTEMPERATUREENTRGYCOArcuateDothalamTRHSomatostatinPITUITARYDownloadedfrom:StudentConsult(on27January200809:43PM)2005Elsevier
Regulation of thyroid hormone secretion Downloaded from: StudentConsult (on 27 January 2008 09:43 PM) ©2005 Elsevier
EtiologyTHTROIDDYSGENESIS80-85%AplasiaHypoplasiaEctopic thyroidSubl5%DYSHORMONOGENESISLnyHyoidbooTSH unresponsivenessPrelaryrigelodide trapping defectormalthyreOrganification defecttmnDefect in TGLodotyrosine deiodinasedeficiency
THTROID DYSGENESIS 8 0 -8 5 % Aplasia Hypoplasia Ectopic th yroid DYSHORMONOGENESIS 5 % TSH u n resp on siven ess lodide tra p p in g d efect Organification d efect Defect in TG Lodotyrosin e d eiod in a se deficien cy Etiology
EtiologyCENTRAL HYPOTHYROIDISM1 in 100.000 livebirthsHypothalamic-pituiary anomalyPanhypopituitarismIsolated TSHdeficiencyTHYROXINERECEPTORRESISTANCEIODINE DEFICIENCYDRUGINDUCEDPTU/Methimazole(MMI)/IodineMATERNALANTIBODYINDUCEDthyrotrophin receptor blockingantibody(TRBAb)
CENTRAL HYPOTHYROIDISM 1 in 100,000 livebirths Hypothal ami c -pit ui ary anomal y Panhypopi t ui t ari s m I s ol at e d TSH deficiency THYROXINE RECEPTOR RESISTANCE IODINE DEFICIENCY DRUG INDUCED PTU / Methimazole (MMI)/Iodi ne MATERNAL ANTIBODY INDUCED thyrot rophi n rece pt o r blocking antibody(TRBAb) Etiology