title: Development of erythroid colony-forming cells in rat fetal spleen: apparent lack of sensitivity to an in vivo corticosteroid excess as compared to fetal liver.
abstract: The development of splenic erythroid colony-forming cells from rat embryos in the last 4 days of intrauterine life was examined after 2 and 7 days in a methylcellulose culture system. The number of 2- and 7-day erythroid colonies decreased sharply between, respectively, days 20 and 21 of gestation and days 19 and 20. Concomitantly, a maturation of proerythroblasts and basophilic erythroblasts to mature erythroblasts was detected on smears of splenic cellular suspensions. The effect of a corticosteroid excess induced by a maternal laparotomy was tested on spleen and liver cultures from the same control or experimental fetuses. The ratio of the number of 2-day to the number of 7-day erythroid colonies did not differ in experimental and control splenic cultures, but in liver cultures was significantly lower at days 19 and 20 in experimental than in control cultures.
mesh_terms: D000305:Adrenal Cortex Hormones / Q000378:metabolism*; D000818:Animals; D002478:Cells, Cultured; D005314:Embryonic and Fetal Development; D004920:Erythropoiesis / Q000187:drug effects*; D005865:Gestational Age; D006412:Hematopoietic Stem Cells / Q000187:drug effects; D008099:Liver / Q000187:drug effects / Q000196:embryology; D051381:Rats; D011919:Rats, Inbred Strains; D013154:Spleen / Q000166:cytology / Q000187:drug effects / Q000196:embryology*
chemical_list: D000305:Adrenal Cortex Hormones