title: Vitamin D metabolite-binding proteins in human tissue.
abstract: Serum and post-microsomal supernatants of human lymphocyte, erythrocyte, skeletal muscle and parathyroid adenoma homogenates were examined for specific binding of 25-hydroxycholecalciferol (25-OHD3) and 1, 25-dihydroxycholecalciferol (1,25-(OH)2D3). Muscle, lymphocytes and parathyroid adenomata extracts contained a 6-S 25-OHD3-binding protein which was not found in erythrocyte extracts, and which was distinct from the smaller serum transport alpha-globulin. A cathodal, 1, 25-(OH)2D3-binding protein, which sedimented at 3-4 S was also detected in parathyroid tissue. These observations suggest the possibility of direct physiologic interaction between vitamin D metabolites and nucleated human tissues other than intestine and bone.
mesh_terms: D000236:Adenoma / Q000378:metabolism; D002352:Carrier Proteins / Q000302:isolation & purification / Q000378:metabolism*; D004100:Dihydroxycholecalciferols / Q000378:metabolism*; D004912:Erythrocytes / Q000378:metabolism; D006801:Humans; D006887:Hydroxycholecalciferols / Q000378:metabolism*; D008214:Lymphocytes / Q000378:metabolism; D009132:Muscles / Q000378:metabolism; D009928:Organ Specificity; D010282:Parathyroid Neoplasms / Q000378:metabolism
chemical_list: D002352:Carrier Proteins; D004100:Dihydroxycholecalciferols; D006887:Hydroxycholecalciferols