The unique action for bone metabolism of 1 alpha,25-(OH)2D3-26,23-lactone.
[23 (S), 25 (R)]-1 alpha,25-Dihydroxyvitamin D3-26,23-lactone [( 23 (S),25 (R)]-1 alpha,25-(OH) 2D3-26,23-lactone) increased dose-dependently alkaline phosphatase activity in osteoblastic cells, clone MC3T3-E1, in medium containing 0.1% bovine serum albumin. The maximal stimulated enzyme activity per mg protein was 1.6-fold over that of control cultures at 250 pg/ml. The metabolite also increased collagen synthesis in a dose-related fashion. On the other hand, [23 (S),25 (R)]-1 alpha,25-(OH)2D3-26,23-lactone decreased slightly but significantly 45Ca mobilization, and blocked the resorptive action of 1 alpha,25-dihydroxyvitamin D3 but not that of parathyroid hormone, in mouse calvaria in organ culture. These results indicate that [23 (S),25 (R)]-1 alpha, 25-(OH)2D3-26,23-lactone stimulates the differentiation of osteoblasts and inhibits bone resorption in vitro.
D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D001862:Bone Resorption / Q000187:drug effects; D001842:Bone and Bones / Q000187:drug effects* / Q000378:metabolism; D002117:Calcitriol / Q000031:analogs & derivatives* / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism; D002999:Clone Cells; D003094:Collagen / Q000096:biosynthesis; D004247:DNA / Q000378:metabolism; D051379:Mice; D009924:Organ Culture Techniques; D010281:Parathyroid Hormone / Q000494:pharmacology; D011506:Proteins / Q000378:metabolism
D010281:Parathyroid Hormone; D011506:Proteins; C026947:1,25-dihydroxyvitamin D3-26,23-lactone; D003094:Collagen; D004247:DNA; D000469:Alkaline Phosphatase; D002117:Calcitriol; D002118:Calcium