Estrogen-stimulated uptake of plasminogen by the mouse uterus.
Administration of a single low dose of estradiol to the immature (4- to 5-week-old) female mouse caused a rapid, uterine-specific increase in the uptake of radiolabeled plasminogen from plasma. A significant increase in uptake was detectable within 30 min and reached a maximum 2-4 h after administration of the hormone. After 4 h, a substantial amount (42%) of the newly taken up plasminogen was found in the uterine lumen. Half-maximal stimulation of uptake occurred at a dose of 0.20 microgram estradiol/animal. Estrogen stimulation of uptake was not blocked by puromycin, indicating that new protein synthesis was not required. Similar results were obtained with mouse plasma albumin. Estrogen-stimulated uptake was not blocked by indomethacin (10 micrograms/g BW, iv), but was blocked by prednisolone. Approximately 50% inhibition of the stimulation induced by 0.5 microgram estradiol in these 10-g animals was accomplished with 50 micrograms prednisolone. This study extends our initial findings on the estrogen-stimulated uptake of plasma proteins by the mouse uterus and provides a mechanism by which uterine plasminogen levels can be elevated before implantation.
D000244:Adenosine Diphosphate / Q000494:pharmacology; D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D004958:Estradiol / Q000494:pharmacology*; D005260:Female; D007213:Indomethacin / Q000494:pharmacology; D007700:Kinetics; D051379:Mice; D010958:Plasminogen / Q000378:metabolism*; D010974:Platelet Aggregation / Q000187:drug effects; D014599:Uterus / Q000187:drug effects / Q000378:metabolism*
D004958:Estradiol; D000244:Adenosine Diphosphate; D010958:Plasminogen; D007213:Indomethacin