title: An in vitro bioassay for 1,25-dihydroxyvitamin D3 and other antirachitic agents.
abstract: Duodenal tissue from chicken embryos (19 days in ovo) has been maintained in organ culture for 48 hours. The incubation medium and culture conditions were chosen to produce a linear relationship between calcium binding protein production and the logarithm of the dose of vitamin D3 steroid in the medium. The dose-response curves are parallel for vitamin D3 and both its major metabolites, 25-hydroxyvitamin D3 and 1,25-dihydroxyVITAMIN D3. The minimum concentration of 1,25-dihydroxyvitamin D3 capable of inducing calcium-binding-protein synthesis was 1 X 10(-9) M.
mesh_terms: D000818:Animals; D001681:Biological Assay; D002118:Calcium / Q000378:metabolism; D002352:Carrier Proteins / Q000096:biosynthesis / Q000378:metabolism; D002642:Chick Embryo; D004100:Dihydroxycholecalciferols / Q000032:analysis* / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004386:Duodenum / Q000187:drug effects / Q000378:metabolism; D006887:Hydroxycholecalciferols / Q000032:analysis* / Q000494:pharmacology; D009924:Organ Culture Techniques; D014176:Protein Biosynthesis / Q000187:drug effects
chemical_list: D002352:Carrier Proteins; D004100:Dihydroxycholecalciferols; D006887:Hydroxycholecalciferols; D002118:Calcium