title: Effects of 25-hydroxyvitamin D3 and 1,25-dihydroxyvitamin D3 on embryonic chick bone in organ culture.
abstract: The ability of embryonic chick bone to respond to 25 hydroxyvitamin D3 and 1,25 dihydroxyvitamin D3 was assessed in organ culture. These metabolites were added to prelabeled chick embryo long-bone explants, and the amount of calcium-45 released into the medium after 24 or 48 h of hormone exposure was measured. For each time period a significant release of calcium-45 from hormone-treated bones was observed. The response to 25 hydroxyvitamin D3 and 1,25 dihydroxyvitamin D3 was always greater at 48 h and a clear dose-dependency was established at this time as well. 1,25 dihydroxyvitamin D3 was the more potent resorbing agent at all concentrations tested. The results from this study suggest that vitamin D metabolites may be involved in bone regulation in the chick embryo.
mesh_terms: D000818:Animals; D001842:Bone and Bones / Q000187:drug effects / Q000196:embryology* / Q000378:metabolism; D002112:Calcifediol / Q000494:pharmacology*; D002117:Calcitriol / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism; D002642:Chick Embryo; D007700:Kinetics; D009924:Organ Culture Techniques
chemical_list: D002117:Calcitriol; D002112:Calcifediol; D002118:Calcium