COMPARISON OF EQUILIBRIUM AND DISEQUILIBRIUM ASSAY CONDITIONS FOR ERGOCALCIFEROL, CHOLECALCIFEROL AND THEIR MAJOR METABOLITES
COMPARISON OF EQUILIBRIUM AND DISEQUILIBRIUM ASSAY CONDITIONS FOR ERGOCALCIFEROL, CHOLECALCIFEROL AND THEIR MAJOR METABOLITES
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DOI：
10.1016/0022-4731(84)90063-3
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发表时间：
1984-01-01
影响因子：
4.1
通讯作者：
HOLLIS, BW
中科院分区：
文献类型：
--
作者：
HOLLIS, BW
研究了麦角钙化醇、胆钙化醇及其主要代谢物的平衡和不平衡测定条件的比较，以评估 (1) 灵敏度优化 (2) 这些化合物在各自测定中的交叉反应性和 (3) 维生素 D 分子与骨化醇结合蛋白或牛胸腺受体最佳结合的侧链空间要求。不平衡测定条件将骨化醇测定的测定灵敏度提高了 30 倍，将 25-羟基骨化醇和 1,25-二羟基骨化醇测定中的代谢物的灵敏度提高了约 3 倍。麦角钙化醇化合物与测试蛋白质的结合效率均低于其胆钙化醇对应物，但有一种例外。在骨化醇测定中，胆骨化醇对骨化醇结合蛋白的亲和力比麦角骨化醇更大。在 25-羟基骨化醇测定中，对骨化醇结合蛋白的亲和力为 25-羟基胆钙化醇 = 24,25-二羟基胆钙化醇 > 25-羟基麦角钙化醇 > 25S,26-二羟基胆钙化醇 > 24,25-二羟基麦角钙化醇 > 25,26-二羟基麦角钙化醇。在 1,25-二羟基骨化醇测定中，牛胸腺受体同等地识别 1,25-二羟基麦角钙化醇和 1,25-二羟基胆钙化醇。从即将到来的数据看来，骨化醇侧链上的羟基和/或甲基改变了这些生理化合物与骨化醇结合蛋白结合的能力。
The comparison of equilibrium and disequilibrium assay conditions for ergocalciferol, cholecalciferol and their major metabolites were investigated to evaluate (1) optimization of sensitivity (2) crossreactivity of these compounds in their respective assays and (3) side chain steric requirements of the vitamin D molecule for optimum binding to the calciferol-binding protein or bovine thymus receptor. Disequilibrium assay conditions improved assay sensitivity 30-fold for the calciferol assay and approximately 3-fold for metabolites in the 25-hydroxycalciferol and 1,25-dihydroxycalciferol assays. Ergocalciferol compounds were uniformly less efficient in their association with the proteins tested than were their cholecalciferol counterparts, with one exception. In the calciferol assay, cholecalciferol had greater affinity for the calciferol-binding protein than did ergocalciferol. In the 25-hydroxycalciferol assay affinity for the calciferol-binding protein was 25-hydroxycholecalciferol = 24,25-dihydroxycholecalciferol > 25-hydroxyergocalciferol > 25S,26-dihydroxycholecalciferol > 24,25-dihydroxyergocalciferol > 25,26-dihydroxyergocalciferol. In the assay for 1,25-dihydroxycalciferol, bovine thymus receptor recognized 1,25-dihydroxyergocalciferol and 1,25-dihydroxycholecalciferol equally. From the forthcoming data in appears that hydroxyl and/or methyl groups on the calciferol side chain alter the ability of these physiological compounds to associate with the calciferol-binding protein.