title: Hormonal control of the in vitro uptake of [35S]sulfate by cartilage of Xenopus laevis tadpoles.
abstract: The influence of various mammalian hormones and growth factors on the skeletal growth in the clawed toad was examined in vitro by monitoring the uptake of [35S]sulfate by tadpole's hindlimbs. Autoradiographic studies demonstrated that the isotope was mainly incorporated into the cartilage. Sulfate uptake was significantly stimulated by 13 nM insulin-like growth factor I (IGF-I) in all experiments. The effect of 13 nM IGF-II was statistically significant only in approximately 50% of the experiments. Insulin was inconsistently effective. A significant stimulation was found using 1300 nM insulin. Neither prolactin and growth hormone nor the thyroid hormones thyroxine and triiodothyronine affected the [35S]sulfate uptake in vitro. The results indicate that cartilage growth in amphibians is mainly stimulated by IGF-I and to a less extended by IGF-II like in mammals.
authors.affiliation: Department of Zoology II, University of Karlsruhe, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Schneider
authors.forename: W
authors.initials: W
authors.lastname: Hanke
mesh_terms: D000818:Animals; D001345:Autoradiography; D002356:Cartilage / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D013006:Growth Hormone / Q000494:pharmacology; D006614:Hindlimb; D006801:Humans; D066298:In Vitro Techniques; D007328:Insulin / Q000494:pharmacology; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology*; D007335:Insulin-Like Growth Factor II / Q000494:pharmacology*; D007814:Larva / Q000254:growth & development; D011388:Prolactin / Q000494:pharmacology; D011994:Recombinant Proteins / Q000494:pharmacology; D013431:Sulfates / Q000378:metabolism*; D013462:Sulfur Radioisotopes; D013963:Thyroid Hormones / Q000494:pharmacology; D014982:Xenopus laevis
chemical_list: D007328:Insulin; D011994:Recombinant Proteins; D013431:Sulfates; D013462:Sulfur Radioisotopes; D013963:Thyroid Hormones; D007334:Insulin-Like Growth Factor I; D007335:Insulin-Like Growth Factor II; D011388:Prolactin; D013006:Growth Hormone