HUMAN-SERUM BINDING-CAPACITY AND AFFINITY FOR 25-HYDROXYERGOCALCIFEROL AND 25-HYDROXYCHOLECALCIFEROL
HUMAN-SERUM BINDING-CAPACITY AND AFFINITY FOR 25-HYDROXYERGOCALCIFEROL AND 25-HYDROXYCHOLECALCIFEROL
复制标题
DOI：
10.1210/jcem-43-1-86
复制
发表时间：
1976-01-01
影响因子：
5.8
通讯作者：
ROJANASATHIT, S
中科院分区：
文献类型：
--
作者：
HADDAD, JG;HILLMAN, L;ROJANASATHIT, S
25-羟基维生素D结合能力和亲和力进行了研究，在人脐带，成人和母亲的血清，并在妇女接受口服避孕药，在体外饱和度分析采用葡聚糖涂层的活性炭吸附未结合的甾醇。25-羟基麦角钙化醇和25-羟基胆钙化醇从人血清结合位点置换3 H25-羟基胆钙化醇的能力相等。在0.5度。C中，25-羟基胆钙化醇的血清结合的表观Kd为8 × 10 - 6。10-10米脐带血和成人血清具有相似的25-羟基胆钙化醇结合能力（1.8 × 10 - 6）。10-6 M），但孕妇血清和口服避孕药的妇女血清的结合能力显着较高。在生理血清浓度的25-羟基维生素D（5 × 10 - 6）下，10-8 M）仅2-3%的人血清25-羟基维生素D结合位点被占据。
25-Hydroxyvitamin D-binding capacity and affinity were studied in human cord, adult and maternal sera, and in sera from women receiving oral contraceptives, by in vitro saturation analyses employing dextran-coated charcoal to adsorb unbound sterol. 25-Hydroxyergocaliferol and 25-hydroxycholecalciferol were equipotent in their ability to displace 3H25-hydroxycholecalciferol from human serum binding sites. At 0.degree. C the apparent Kd for the serum binding of 25-hydroxycholecalciferol was 8 .times. 10-10 M. Cord and adult sera had a similar 25-hydroxycholecalciferol binding capacity (1.8 .times. 10-6 M), but the binding capacity of maternal sera and the sera from women receiving oral contraceptives was significantly higher. At physiological serum concentrations of 25-hydroxyvitamin D (5 .times. 10-8 M) only 2-3% of human serum 25-hydroxyvitamin D-binding sites are occupied.