title: Feedback regulation of 25-hydroxycholecalciferol metabolism by vitamin D3.
abstract: 1. In vitamin D-deficient chicks both vitamin D3 and 1alpha-hydroxycholecalciferol markedly decrease renal 1-hydroxylase activity and induce 24-hydroxylase activity. 2. Actinomycin D abolishes both effects. 3. These results are consistent with feedback regulation of vitamin D3 metabolism by a direct nuclear action of the vitamin or its metabolites on the kidney cells.
mesh_terms: D000818:Animals; D002645:Chickens; D002762:Cholecalciferol / Q000494:pharmacology*; D003609:Dactinomycin / Q000494:pharmacology; D006887:Hydroxycholecalciferols / Q000378:metabolism*; D007668:Kidney / Q000187:drug effects / Q000201:enzymology; D013250:Steroid Hydroxylases / Q000378:metabolism; D014808:Vitamin D Deficiency / Q000378:metabolism
chemical_list: D006887:Hydroxycholecalciferols; D002762:Cholecalciferol; D003609:Dactinomycin; D013250:Steroid Hydroxylases