title: Corticotrophin-releasing factor and urocortin inhibit system A activity in term human placental villous explants.
abstract: Plasma corticotrophin-releasing factor (CRF) and urocortin are elevated in preterm labour and/or fetal growth restriction (FGR). FGR is associated with reduced placental system A amino acid transporter activity and in vitro data suggest altered endocrine status could be responsible. Here we test the hypothesis that CRF and urocortin inhibit placental system A activity. Chronic (48h) exposure of term placental villous explants to these hormones (10(-7)M) significantly reduced system A activity (Na(+)-dependent (14)C-methylaminoisobutyric acid uptake), whereas 1h exposure had no effect. We propose elevated CRF and urocortin contribute to FGR through negative regulation of placental system A activity.
authors.affiliation: Department of Pediatrics, Obstetrics and Reproductive Medicine, Section of Obstetric and Gynecology, University of Siena, Siena, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Giovannelli
authors.forename: S L
authors.initials: SL
authors.lastname: Greenwood
authors.forename: M
authors.initials: M
authors.lastname: Desforges
authors.forename: C P
authors.initials: CP
authors.lastname: Sibley
authors.forename: F
authors.initials: F
authors.lastname: Petraglia
mesh_terms: D026924:Amino Acid Transport System A / Q000378:metabolism*; D001706:Biopsy; D002478:Cells, Cultured; D006063:Chorionic Gonadotropin / Q000494:pharmacology; D002824:Chorionic Villi / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D003346:Corticotropin-Releasing Hormone / Q000494:pharmacology*; D015536:Down-Regulation; D005260:Female; D005865:Gestational Age; D006801:Humans; D010042:Ouabain / Q000494:pharmacology; D011247:Pregnancy; D047929:Term Birth / Q000378:metabolism / Q000502:physiology; D013997:Time Factors; D054832:Urocortins / Q000494:pharmacology*
chemical_list: D026924:Amino Acid Transport System A; D006063:Chorionic Gonadotropin; D054832:Urocortins; D010042:Ouabain; D003346:Corticotropin-Releasing Hormone