title: Effects of vitamin D3 metabolites on bone cell calcium transport.
abstract: The vitamin D3 metabolite, 25-hydroxycholecalciferol, at concentrations of 0.01 to 10.0 microgram/ml, decreased calcium uptake by isolated bone cells. The effect occurred within 1 min after the simultaneous addition of metabolite and 45Ca. Lactic acid and ATP production by the cells was not affected. 24(R), 25-dihydroxycholecalciferol produced a similar decrease in calcium uptake. Vitamin D3 had no effect at concentrations from 0.01 to 10.0 micrograms/ml. No effect of 1,25-dihydroxycholecalciferol on calcium uptake was observed with concentrations from 0.1 to 100 ng/ml and various preincubation periods extending to 2 h. None of the agents had any effect on calcium efflux. The effects of 25-hydroxycholecalciferol and 24(R), 25-dihydroxycholecalciferol on calcium uptake were not seen in isolated fetal rat skin cell preparations.
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D001692:Biological Transport / Q000187:drug effects; D001842:Bone and Bones / Q000166:cytology / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism*; D002478:Cells, Cultured; D002762:Cholecalciferol / Q000494:pharmacology*; D004100:Dihydroxycholecalciferols / Q000494:pharmacology; D006887:Hydroxycholecalciferols / Q000494:pharmacology; D007460:Iodoacetamide / Q000494:pharmacology; D007773:Lactates / Q000378:metabolism; D012867:Skin / Q000378:metabolism
chemical_list: D004100:Dihydroxycholecalciferols; D006887:Hydroxycholecalciferols; D007773:Lactates; D002762:Cholecalciferol; D000255:Adenosine Triphosphate; D002118:Calcium; D007460:Iodoacetamide