title: Human placental ecto-enzymes: studies on the plasma membrane anchorage and effect of inhibitors of ATP-metabolizing enzymes.
abstract: The human placental microvillar membrane contains several ectoenzymes, including 5'-nucleotidase, alkaline phosphatase and ATP-diphosphohydrolase (ATP-DPH), which might be involved in the extracellular metabolism of nucleotides. The type of anchorage to the plasma membrane of the two first enzymes has been shown to be via a glycosyl-phosphatidylinositol. In the present study, using an enzymatic approach, we show that the ATP-DPH should be attached to the plasma membrane through a different type of anchorage. We were also interested in the search of compounds which could interact differentially with this enzyme to be used as a tool for studying the other two hydrolytic enzymes in the presence of ATP-DPH. Here we report several inhibitors of ecto-ATPases which seem to be a useful tool for studying these three enzymes.
authors.affiliation: Dept. de Bioquímica y Biología Molecular, Fac. Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile.
authors.forename: L
authors.initials: L
authors.lastname: Chayet
authors.forename: L
authors.initials: L
authors.lastname: Collados
authors.forename: A M
authors.initials: AM
authors.lastname: Kettlun
authors.forename: E
authors.initials: E
authors.lastname: Campos
authors.forename: A
authors.initials: A
authors.lastname: Traverso-Cori
authors.forename: L
authors.initials: L
authors.lastname: García
authors.forename: M A
authors.initials: MA
authors.lastname: Valenzuela
mesh_terms: D015720:5'-Nucleotidase / Q000032:analysis* / Q000378:metabolism; D000469:Alkaline Phosphatase / Q000032:analysis* / Q000378:metabolism; D000639:Amitriptyline / Q000494:pharmacology; D001081:Apyrase / Q000032:analysis* / Q000037:antagonists & inhibitors / Q000378:metabolism; D002110:Caffeine / Q000494:pharmacology; D002462:Cell Membrane / Q000187:drug effects / Q000201:enzymology / Q000648:ultrastructure; D010450:Endopeptidases / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005260:Female; D005476:Fluphenazine / Q000494:pharmacology; D017261:Glycosylphosphatidylinositols / Q000378:metabolism; D006801:Humans; D008012:Lidocaine / Q000494:pharmacology; D008871:Microvilli / Q000187:drug effects / Q000201:enzymology / Q000648:ultrastructure; D009711:Nucleotides / Q000378:metabolism; D043265:Phosphatidylinositol Diacylglycerol-Lyase; D010739:Phospholipase D / Q000494:pharmacology; D010920:Placenta / Q000187:drug effects / Q000201:enzymology* / Q000648:ultrastructure; D010738:Type C Phospholipases / Q000494:pharmacology
chemical_list: D004791:Enzyme Inhibitors; D017261:Glycosylphosphatidylinositols; D009711:Nucleotides; D000639:Amitriptyline; D002110:Caffeine; D008012:Lidocaine; D000469:Alkaline Phosphatase; D015720:5'-Nucleotidase; D010738:Type C Phospholipases; D010739:Phospholipase D; D010450:Endopeptidases; D001081:Apyrase; D043265:Phosphatidylinositol Diacylglycerol-Lyase; D005476:Fluphenazine