Sengupta A, Hage D S
Chemistry Department, University of Nebraska, Lincoln 68588-0304, USA.
Anal Chem. 1999 Sep 1;71(17):3821-7. doi: 10.1021/ac9903499.
This study used high-performance affinity chromatography (HPAC) and immobilized human serum albumin (HSA) columns to examine the specificity and cross-reactivity of various compounds that have been proposed as markers for the minor binding sites of HSA. These agents included acetyldigitoxin and digitoxin as probes for the digitoxin site, phenol red as a probe for the bilirubin site, and cisor trans-clomiphene as markers for the tamoxifen site. None of these probes showed any significant binding at HSA's indole-benzodiazepine site. However, phenol red did bind at the warfarin-azapropazone site of HSA, and cis/trans-clomiphene gave positive allosteric effects caused by the binding of warfarin to HSA. Digitoxin and acetyldigitoxin were found to bind to a common, unique region on HSA; cis- and trans-clomiphene also appeared to interact at a unique site, although trans-clomiphene displayed additional direct competition with phenol red. From these results it was possible to develop a model that described the general relationship between these binding regions on HSA. This information should be useful in future studies that employ HPAC for characterizing the binding of HSA to other drugs or clinical agents.
本研究使用高效亲和色谱法（HPAC）和固定化人血清白蛋白（HSA）柱，来检测各种被提议作为HSA次要结合位点标志物的化合物的特异性和交叉反应性。这些试剂包括作为洋地黄毒苷位点探针的乙酰洋地黄毒苷和洋地黄毒苷、作为胆红素位点探针的酚红，以及作为他莫昔芬位点标志物的顺式或反式克罗米芬。这些探针在HSA的吲哚 - 苯二氮䓬位点均未显示出任何显著结合。然而，酚红确实在HSA的华法林 - 阿扎丙宗位点结合，并且顺式/反式克罗米芬产生了由华法林与HSA结合引起的正变构效应。发现洋地黄毒苷和乙酰洋地黄毒苷与HSA上一个共同的独特区域结合；顺式和反式克罗米芬似乎也在一个独特位点相互作用，尽管反式克罗米芬与酚红还存在额外的直接竞争。根据这些结果，有可能建立一个描述HSA上这些结合区域之间一般关系的模型。这些信息对于未来利用HPAC表征HSA与其他药物或临床试剂结合的研究应该是有用的。
