title: Thyroid hormones in the skeletogenesis and accessory sources of endogenous hormones in Xenopus laevis (Amphibia; Anura) ontogeny: Experimental evidence.
abstract: Skeletal development was studied in normal and goitrogen-treated Xenopus laevis tadpoles reared under thyroid hormone (TH) deficiency. Early stages of skeletal development proceed similarly in both groups. Later stages are retarded or completely arrested in goitrogen-treated tadpoles. After goitrogen-treated tadpoles were transferred into pure water or into a medium containing both goitrogen and exogenous TH, tadpoles resumed development. Consequently, late stages of skeletogenesis are TH-dependent and TH-induced. Athyroid X. laevis "giant tadpoles" described in literature differ from goitrogen-arrested tadpoles in that they have features which require TH to appear. The appearance of TH-depended features in giant tadpoles indicates the occurrence of the additional sources of TH other than thyroid gland.
authors.affiliation: Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, Leninskii pr. 33, Moscow, 119071, Russia, evol_morphol_lab@mail.ru.
authors.forename: S V
authors.initials: SV
authors.lastname: Smirnov
authors.forename: A B
authors.initials: AB
authors.lastname: Vassilieva
mesh_terms: D000818:Animals; D007814:Larva / Q000187:drug effects; D010012:Osteogenesis; D013890:Thiourea / Q000494:pharmacology; D013963:Thyroid Hormones / Q000172:deficiency / Q000378:metabolism*; D014982:Xenopus laevis / Q000196:embryology / Q000254:growth & development / Q000378:metabolism*
chemical_list: D013963:Thyroid Hormones; D013890:Thiourea