Plasminogen activator production by trophoblast cells in vitro: Effect of steroid hormones and protein synthesis inhibitors

摘要: Variations in the production of plasminogen activator (PA), a proteolytic enzyme that has been associated with trophoblast invasiveness, may be critical to success or failure placentation. To understand better mechanisms regulating PA we have cultured human cells and measured effect steroid hormones protein synthesis inhibitors upon their capacity lyse 125 l-fibrinogen. Progesterone (P) 17 β -estradiol (E 2 ) at concentrations 10 −8 M, −7 −5 M did not cause significant changes chorionic gonadotropin (hCG) by cells. In contrast, dexamethasone (10 M) caused significant, dose-dependent decrease production. There was no difference hCG between cultures treated cytosine arabinoside (1mg/ml) untreated cultures. When actinomycin D (0.5 μ g/ml) added time zero, during first 24hours incubation significantly different from After 24hours, however, disappeared actinomycin-treated while both substances continued released controls. These experiments indicate trophobiastic vitro are independent DNA replication under P E control. They also show stored within into medium incubation; after this period presence represents de novo synthesis. The data suggest that, similar hCG, is produced continuously as long cell functionally active.