title: Circadian variation in teratogenic response to dexamethasone in mice.
abstract: The frequency of dexamethasone-induced cleft palate in mouse fetuses was studied at four fixed times on day 13 of gestation. On day 18, the fetuses were examined for malformations and corticosterone concentration was additionally measured. Evidence of a diurnal rhythm in cleft palate frequency, as well as in corticosterone level was obtained. A reciprocal relationship thereby exists. An increase in the teratogenicity was observed during the dark phase until transition from dark to light. This transition is associated with a decrease in corticosterone.
mesh_terms: D000818:Animals; D002940:Circadian Rhythm; D003345:Corticosterone / Q000097:blood; D003907:Dexamethasone / Q000633:toxicity*; D004622:Embryo, Mammalian / Q000187:drug effects; D005260:Female; D005938:Glucocorticoids / Q000494:pharmacology; D051379:Mice; D008815:Mice, Inbred Strains; D011247:Pregnancy; D013723:Teratogens; D013997:Time Factors
chemical_list: D005938:Glucocorticoids; D013723:Teratogens; D003907:Dexamethasone; D003345:Corticosterone