Separation of thyroxine(T4)-binding proteins of human serum in polyacrylamide gel at pH 7.4. I. Effect of pH on distrubution of tracer quantities of T4.
Separation of thyroxine(T4)-binding proteins of human serum in polyacrylamide gel at pH 7.4. I. Effect of pH on distrubution of tracer quantities of T4.
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在 pH 7.4 的聚丙烯酰胺凝胶中分离人血清的甲状腺素 (T4) 结合蛋白。
DOI：
10.1210/jcem-30-2-237
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发表时间：
1970
期刊：
影响因子：
--
通讯作者：
R. I. Gregerman
中科院分区：
文献类型：
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作者：
P. Davis;R. I. Gregerman
用哌嗪-N，N′-双-（2-乙磺酸）（PIPES）缓冲的聚丙烯酰胺凝胶电泳系统，在生理pH条件下，能分离甲状腺素结合球蛋白（TBG）、白蛋白和甲状腺素结合前白蛋白（TBPA）。在该系统中，在示踪水平的甲状腺素（T4）下，TBG在pH7.4比在pH9.0（Tris-硼酸盐缓冲液）下结合T4多50%。然而，结合T4 TBPA减少在生理pH值，但在碱性pH值高。TBPA结合的pH依赖性证实了以前报道的琼脂糖电泳研究。T4结合的pH值依赖性的特定蛋白质的结合数据先前报道的各种电泳系统的部分解释的差异。T4的白蛋白结合基本上不受pH值变化的影响。注意到T4的一致的、高度个体化的TBG后区域迁移（范围：4-15%），这归因于对甲状腺素亲和力相对较低的蛋白质与激素的结合。后TBG区域绑定O.
ABSTRACT A polyacrylamide gel electrophoresis system buffered with piperazine-N,N′-bis-(2-ethane sulfonic acid) (PIPES) has been shown to be capable of resolving thyroxine-binding globulin (TBG), albumin and thyroxine-binding prealbumin (TBPA) at physiologic pH. In this system at tracer levels of thyroxine (T4), TBG binds 50% more T4 at pH 7.4 than at pH 9.0 (Tris-borate buffer). Inversely, binding of T4 by TBPA was reduced at physiologic pH but high at alkaline pH. The pH-dependence of TBPA binding confirms previously reported electrophoretic studies in agarose. The pH-dependence of T4 binding by the hormone-specific proteins explains in part disparities in binding data previously reported from various electrophoretic systems. Albumin binding of T4 was not substantially affected by changes of pH. Consistent, highly individualized post-TBG zone migration of T4 (range: 4–15%) was noted and was attributed to binding of hormone by proteins with relatively low affinities for thyroxine. Post-TBG zone binding o...