title: The local origin of decidual cells in pregnant mice.
abstract: In order to evaluate the participation of extrauterine cells in the formation of mouse antimesometrial decidua, [3H]-thymidine was administered ip on days 1, 5 and 6 of pregnancy and the animals were killed 1 h afterwards. A second group of mice received four ip injections of [3H]-thymidine at 6-h intervals on the 1st day of pregnancy and were killed on the 2nd, 5th or 6th day of pregnancy. A third group of virgin mice in estrus received [3H]-thymidine ip four times at 6-h intervals and was killed 96 h after the first injection. Radioautographs of the uteri showed that few endometrial stromal cells were labelled on the 1st and 2nd day of pregnancy. Although many decidual cells incorporated thymidine on the 5th and 6th day of pregnancy in pulse-labelled animals, only few labelled decidual cells were found on the 5th and 6th day of pregnancy in animals that received several injections of thymidine on the 1st and 2nd day of pregnancy. These results indicate that the antimesometrial decidual cells that develop at the beginning of pregnancy are mostly of local origin. The short-term migration of extraneous cells into the uterus to participate in decidualization is not supported by these data.
mesh_terms: D000818:Animals; D001345:Autoradiography; D002465:Cell Movement; D003656:Decidua / Q000166:cytology*; D005260:Female; D051379:Mice; D008815:Mice, Inbred Strains; D011247:Pregnancy; D013936:Thymidine / Q000031:analogs & derivatives / Q000378:metabolism; D014316:Tritium; D014599:Uterus / Q000166:cytology
chemical_list: D014316:Tritium; C012439:methylthymidine; D013936:Thymidine