title: Synthesis and biologic activity of 3 beta-thiovitamin D3.
abstract: We synthesized 3 beta-thiovitamin D3 from 7-dehydrocholesterol and tested its biological activity and protein binding properties. The thiovitamin was found to be a weak vitamin D agonist at high doses in vivo. It was poorly bound by both vitamin D-binding protein as well as by the intestinal cytosol receptor for 1,25-dihydroxyvitamin D. It did not increase the synthesis of calcium binding protein in the chick embryonic duodenum and did not block the activity of 1,25-dihydroxyvitamin D3 in this system. We conclude that 3 beta-thiovitamin D3 is a weak vitamin D agonist in vivo with no agonist activity or antagonist activity to 1,25-dihydroxyvitamin D3 in the chick embryonic duodenum.
authors.forename: J M
authors.initials: JM
authors.lastname: Londowski
authors.forename: L K
authors.initials: LK
authors.lastname: Revelle
authors.forename: S B
authors.initials: SB
authors.lastname: Kost
authors.forename: R A
authors.initials: RA
authors.lastname: Corradino
authors.forename: R
authors.initials: R
authors.lastname: Kumar
mesh_terms: D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D002117:Calcitriol / Q000378:metabolism / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism; D055598:Chemical Phenomena; D002621:Chemistry; D002642:Chick Embryo; D002762:Cholecalciferol / Q000138:chemical synthesis / Q000378:metabolism / Q000494:pharmacology* / Q000031:analogs & derivatives; D004386:Duodenum / Q000378:metabolism; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000187:drug effects; D008297:Male; D009924:Organ Culture Techniques; D051381:Rats; D018167:Receptors, Calcitriol; D011987:Receptors, Steroid / Q000378:metabolism; D014809:Vitamin D-Binding Protein / Q000378:metabolism
chemical_list: D018167:Receptors, Calcitriol; D011987:Receptors, Steroid; D014809:Vitamin D-Binding Protein; D002762:Cholecalciferol; C046226:3-thiovitamin D3; D002117:Calcitriol; D002118:Calcium