TURNOVER OF THE PLASMA-BINDING PROTEIN FOR VITAMIN-D AND ITS METABOLITES IN NORMAL HUMAN-SUBJECTS
TURNOVER OF THE PLASMA-BINDING PROTEIN FOR VITAMIN-D AND ITS METABOLITES IN NORMAL HUMAN-SUBJECTS
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DOI：
10.1210/jcem-53-6-1110
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发表时间：
1981-01-01
影响因子：
5.8
通讯作者：
GOODMAN, DS
中科院分区：
文献类型：
--
作者：
KAWAKAMI, M;BLUM, CB;GOODMAN, DS
本文观察了4名正常青年人血浆维生素D及其代谢产物结合蛋白（DBP）的周转。每例受试者静脉注射125 I标记的DBP，并在随后的15-18天内测定血浆比放射性-时间曲线。在研究期间收集所有尿液，并确定累积尿125 I排泄曲线。采用加权、最小二乘、非线性回归技术，通过房室分析分析血清和尿液放射性数据。在研究的每例受试者中，3个样本池模型提供了与血清特异性放射性-时间数据的最佳拟合。基于生理学考虑，选择了3池、悬链线模型。通过假设从合并液1到碘化物隔室的单次流出来拟合尿液数据。全身交换性DBP平均为2.89 g。在研究的受试者中，DBP的产生率为0.69-0.93 g/天，平均值为10.1 mg/kg体重/天。可以得出关于DBP分子的解剖学定位的推断，所述DBP分子包括模型中的3个池中的每一个。合并液1的质量非常接近血浆室中DBP的计算质量，平均占全身可交换DBP的50%。池1中的DBP包含血管内血浆隔室中的DBP。样本池2略小于样本池1，可能代表血管外细胞外室中的DBP。其他人已经证明，人DBP存在于许多组织中。合并液3，由此处报告的动力学分析鉴定，大小为300 mg，可代表DBP的细胞内区室。
The turnover of the plasma binding protein for vitamin D and its metabolites (DBP) was investigated in 4 normal young men. 125I-Labeled DBP was injected i.v. into each subject, and the plasma specific radioactivity-time curve was determined for the following 15-18 days. All urine was collected during the study, and the cumulative urinary 125I excretion curve was determined. The serum and urinary radioactivity data were analyzed by compartmental analysis using a weighted, least squares, nonlinear regression technique. In each of the subjects studied, a 3 pool model provided the best fit to the serum specific radioactivity-time data. A 3 pool, catenary model was selected on the basis of physiological considerations. The urinary data were fit by assuming a single outflow from pool 1 into an iodide compartment. Total body exchangeable DBP averaged 2.89 g. The production rate of DBP varied from 0.69-0.93 g/day in the subjects studied, with a mean of 10.1 mg/kg body wt per day. Inferences could be drawn about the anatomical localization of the DBP molecules that comprise each of the 3 pools in the model. The mass of pool 1 was very close to the calculated mass of DBP in the plasma compartment and comprised a mean of 50% of the total body exchangeable DBP. DBP in pool 1 comprises DBP in the intravascular plasma compartment. Pool 2, slightly smaller than pool 1, probably represents DBP in the extravascular, extracellular compartment. Others have demonstrated that human DBP is present in many tissues. Pool 3, identified from the kinetic analysis reported here and .apprx. 300 mg in size, may represent the intracellular compartment of DBP.