title: Ontogenic changes in human placental sodium iodide symporter expression.
abstract: The human fetus requires a maternal supply of iodide to synthesize thyroid hormone from 16 weeks gestation. Placental iodide transport is regulated by the sodium iodide symporter (NIS). We studied the ontogeny of NIS in placentas from surgically terminated pregnancies and from normal term pregnancies. NIS mRNA was low at 6 weeks gestation and peaked at 12 weeks gestation. Placental NIS protein levels are significantly correlated with gestational age during early pregnancy and increase with increased placental vascularization. This would lead to increased iodide supply to meet increased fetal requirements for thyroid hormone synthesis as the pregnancy progresses.
authors.affiliation: Conjoint Endocrine Laboratory, Pathology Queensland, Royal Brisbane and Women's Hospital, Herston, 4029 Brisbane, Australia.
authors.forename: H
authors.initials: H
authors.lastname: Li
authors.forename: J
authors.initials: J
authors.lastname: Patel
authors.forename: R H
authors.initials: RH
authors.lastname: Mortimer
authors.forename: K
authors.initials: K
authors.lastname: Richard
mesh_terms: D000328:Adult; D015153:Blotting, Western; D005260:Female; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D010920:Placenta / Q000098:blood supply / Q000378:metabolism*; D021041:Placental Circulation; D010929:Placentation; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011262:Pregnancy Trimester, Second; D012333:RNA, Messenger / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D027981:Symporters / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D047929:Term Birth; D000099209:Sodium-Iodide Symporters
chemical_list: D012333:RNA, Messenger; D027981:Symporters; D000099209:Sodium-Iodide Symporters