title: Stage-specific distribution of P-glycoprotein in first-trimester and full-term human placenta.
abstract: The distribution of P-glycoprotein in human placenta has been examined by immunohistochemistry using a battery of monoclonal antibodies (MRK-16, C219 and JSB-1). P-glycoprotein was located on the syncytiotrophoblast microvillus border in first-trimester placentas and some of the placental macrophages (Hofbauer cells) showed weak cytoplasmic staining. In term placentas, however, staining was not observed in the trophoblast but most of the Hofbauer cells displayed strong cytoplasmic staining. In situ hybridization with specific gene probes suggested that both human multidrug resistance genes were expressed in the placenta, although only the multidrug resistance-1 gene product would have been detected by the MRK and JSB-1 antibodies. These results point to distinct functions for P-glycoprotein during the different stages of placental development and indicate that its expression may be under developmental control.
authors.affiliation: Department of Molecular & Cell Biology, University of Aberdeen, Scotland, UK.
authors.forename: A
authors.initials: A
authors.lastname: MacFarland
authors.forename: D R
authors.initials: DR
authors.lastname: Abramovich
authors.forename: S W
authors.initials: SW
authors.lastname: Ewen
authors.forename: C K
authors.initials: CK
authors.lastname: Pearson
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D002352:Carrier Proteins / Q000032:analysis*; D005314:Embryonic and Fetal Development; D005260:Female; D006801:Humans; D017403:In Situ Hybridization; D008264:Macrophages / Q000737:chemistry; D008562:Membrane Glycoproteins / Q000032:analysis*; D010920:Placenta / Q000737:chemistry*; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D015347:RNA Probes; D014327:Trophoblasts / Q000737:chemistry
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D002352:Carrier Proteins; D008562:Membrane Glycoproteins; D015347:RNA Probes