title: Association of type II apoptosis and 92-kDa type IV collagenase expression in human amniochorion in prematurely ruptured membranes with tumor necrosis factor receptor-1 expression.
abstract: OBJECTIVE
  We assessed the presence of tumor necrosis factor receptor-1 (TNF-R1), apoptosis, and simultaneous expression of 92-kDa collagenase type IV (MMP-9) in samples of human chorioamnion from women with premature rupture of membranes (PROM).
  
  
  METHODS
  Amniotic membranes from women who underwent normal labor, cesarean delivery, or had PROM at term were studied by immunohistochemistry for localization of TNF-R1 and R2. Transmission electron microscopy and DNA fragmentation analyses by agarose gel electrophoresis were performed to identify apoptosis characteristics. Zymography and in situ zymography were used to assess gelatinolytic activity.
  
  
  RESULTS
  We found that TNF-R1 was abundant in membranes from subjects who had normal labor and very abundant in those who had PROM. By contrast TNF-R2 was abundant only in membranes from subjects who had cesarean delivery. Gelatinolytic activity was associated with extracellular matrix rather than cells and was higher in extracts from fetal membranes from PROM and normal labor than in extracts obtained from cesarean deliveries. Transmission electron microscopy of fetal membranes from PROM revealed ultrastructural characteristics in amnion epithelium consistent with type II apoptosis. DNA laddering in agarose gel electrophoresis corroborated results from DNA fragmentation.
  
  
  CONCLUSIONS
  During PROM the fetal membranes undergo type II apoptosis and extracellular matrix degradation in association with TNF-R1 expression.
authors.affiliation: Direction of Research and Electronic Microscopy Department, Instituto Nacional de Perinatologia, Direccion de Investigacion, Montes Urales 800, Mexico, D.F., 11000, Mexico.
authors.forename: Fabian
authors.initials: F
authors.lastname: Arechavaleta-Velasco
authors.forename: Josefina
authors.initials: J
authors.lastname: Mayon-Gonzalez
authors.forename: Marco
authors.initials: M
authors.lastname: Gonzalez-Jimenez
authors.forename: Cesar
authors.initials: C
authors.lastname: Hernandez-Guerrero
authors.forename: Felipe
authors.initials: F
authors.lastname: Vadillo-Ortega
mesh_terms: D000650:Amnion / Q000737:chemistry / Q000201:enzymology / Q000648:ultrastructure; D015703:Antigens, CD / Q000032:analysis*; D017209:Apoptosis; D002585:Cesarean Section; D002823:Chorion / Q000737:chemistry / Q000201:enzymology / Q000648:ultrastructure; D053938:DNA Fragmentation; D004591:Electrophoresis, Polyacrylamide Gel; D004847:Epithelial Cells / Q000737:chemistry; D005321:Extraembryonic Membranes / Q000737:chemistry / Q000201:enzymology*; D005260:Female; D005322:Premature Rupture of Fetal Membranes / Q000378:metabolism*; D006651:Histocytochemistry; D006801:Humans; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism*; D008854:Microscopy, Electron; D008856:Microscopy, Fluorescence; D008970:Molecular Weight; D011247:Pregnancy; D018124:Receptors, Tumor Necrosis Factor / Q000032:analysis*; D047888:Receptors, Tumor Necrosis Factor, Type I; D047889:Receptors, Tumor Necrosis Factor, Type II
chemical_list: D015703:Antigens, CD; D018124:Receptors, Tumor Necrosis Factor; D047888:Receptors, Tumor Necrosis Factor, Type I; D047889:Receptors, Tumor Necrosis Factor, Type II; D020780:Matrix Metalloproteinase 9