title: Modifications of the thymus and splenic thymic dependent zones after in utero exposure to phenytoin: qualitative and quantitative analysis in C3H mice.
abstract: Pregnant female mice were randomly distributed in two groups and received twice a day by gavage either 25 mg/kg Dilantin in 0.2 ml distilled water or 0.2 ml distilled water till full term. The offspring were sacrificed on day 5. In the exposed group, the thymic cortex was reduced with a low mitotic activity in the lymphoid population while reticuloepithelial tissue was enlarged; numerous interdigitated reticular cells accumulate at the cortico/medulla border. In the spleen, the white pulp was enlarged because of lymphocytes accumulation in the periarteriolar sheets. In these two organs, the relative number of Thyl-2+, Lyt 1+ and Lyt 2+ T cell subsets were also modified showing especially a decrease in the thymus and an increase in the spleen of the Lyt 1+ cells. Since at the same time the thymus and the spleen of the females which reproduced the neonates are quite unchanged, it is concluded that the developing immune system of the fetal mouse is more susceptible to diphenylhydantoin than the immune system of the adult. This raises the question of the reversibility of this in utero acquired immune impairment.
mesh_terms: D000818:Animals; D005260:Female; D008431:Maternal-Fetal Exchange; D051379:Mice; D008809:Mice, Inbred C3H; D010672:Phenytoin / Q000493:pharmacokinetics / Q000633:toxicity*; D011247:Pregnancy; D013154:Spleen / Q000187:drug effects* / Q000196:embryology / Q000473:pathology; D013601:T-Lymphocytes / Q000187:drug effects; D013950:Thymus Gland / Q000187:drug effects* / Q000196:embryology / Q000473:pathology
chemical_list: D010672:Phenytoin