Schwartz Z, Soskolne W A, Atkin I, Goldstein M, Ornoy A
Department of Periodontics, Hebrew University Hadassah, Faculty of Dental Medicine, Jerusalem, Israel.
J Bone Miner Res. 1989 Apr;4(2):157-63. doi: 10.1002/jbmr.5650040205.
To examine the effects of 24,25-(OH)2D3 and 1,25-(OH)2D3 on fetal long bone modeling the radii and ulnae of 16 day fetal mice were grown in vitro for 2 days. Their growth, mineralization, and resorption were assessed by measuring diaphyseal length, calcium and phosphorus content, hydroxyproline-protein ratios, and the release of incorporated 45Ca. The results showed that 24,25-(OH)2D3 at concentrations of 10(-10)-10(-8) M stimulated the growth of the bones as indicated by their increased diaphyseal length, periosteal bone area, and hydroxyproline content. Calcium and phosphorus content was significantly increased; 45Ca release was unaltered. Bones incubated in media containing 10(-6) M 24,25-(OH)2D3 responded in a similar fashion to bones incubated in media containing 10(-10)-10(-8) M 1,25-(OH)2D3, with inhibition of bone growth as indicated by reduced diaphyseal length, periosteal bone area, hydroxyproline-protein ratios, and calcium and phosphorus content; 45Ca release was significantly increased. Neither metabolite affected total bone length. The results suggest a role for 24,25-(OH)2D3 in the growth of fetal mice bones in vitro and also confirm the findings from previous studies that 1,25-(OH)2D3 and high concentrations of 24,25-(OH)2D2 stimulate bone resorption.
为研究24,25 - 二羟维生素D3[24,25-(OH)2D3]和1,25 - 二羟维生素D3[1,25-(OH)2D3]对胎儿长骨塑形的影响，将16日龄胎鼠的桡骨和尺骨进行体外培养2天。通过测量骨干长度、钙和磷含量、羟脯氨酸 - 蛋白质比率以及掺入的45Ca释放量来评估它们的生长、矿化和吸收情况。结果显示，浓度为10(-10)-10(-8)M的24,25-(OH)2D3可刺激骨骼生长，表现为骨干长度增加、骨膜骨面积增加以及羟脯氨酸含量增加。钙和磷含量显著增加；45Ca释放量未改变。在含有10(-6)M 24,25-(OH)2D3的培养基中培养的骨骼，其反应与在含有10(-10)-10(-8)M 1,25-(OH)2D3的培养基中培养的骨骼相似，表现为骨骼生长受到抑制，如骨干长度缩短、骨膜骨面积减小、羟脯氨酸 - 蛋白质比率降低以及钙和磷含量降低；45Ca释放量显著增加。两种代谢产物均不影响总骨长度。结果表明24,25-(OH)2D3在体外对胎鼠骨骼生长起作用，同时也证实了先前研究的结果，即1,25-(OH)2D3和高浓度的24,25-(OH)2D2会刺激骨吸收。
