Vermeir M, Vanstapel F, Blanckaert N
Biochem J. 1984 Oct 15;223(2):455-9. doi: 10.1042/bj2230455.
A radioassay for specific determination of the rates of UDP-glucuronic acid-dependent conversion of bilirubin into the two isomeric (C-8, C-12) bilirubin monoglucuronides and bilirubin diglucuronide is described and illustrated by its application to rat liver microsomes. The method is based on measurement of the relative amounts of radiolabel in unesterified bilirubin and its mono- and di-esterified reaction products after incubation with [14C]bilirubin as substrate. This analysis is performed by the alkaline-methanolysis procedure, combined with one of two t.l.c. systems developed in order to enhance the sensitivity, accuracy and precision of the radioassay. Results for rates of total bilirubin glucuronide formation obtained with the new assay and the standard enzyme assay based on the ethyl anthranilate diazo-method were identical. However, the sensitivity of the latter technique is approx. 10-fold lower than that of the radioassay.
本文描述了一种用于特异性测定胆红素在UDP-葡萄糖醛酸依赖性作用下转化为两种异构(C-8,C-12)胆红素单葡萄糖醛酸酯和胆红素二葡萄糖醛酸酯速率的放射分析方法,并通过将其应用于大鼠肝微粒体进行了说明。该方法基于以[14C]胆红素为底物孵育后,测量未酯化胆红素及其单酯和二酯反应产物中放射性标记的相对量。这种分析通过碱性甲醇解程序进行,并结合开发的两种薄层层析系统之一,以提高放射分析的灵敏度、准确性和精密度。用新方法和基于邻氨基苯甲酸乙酯重氮法的标准酶法获得的总胆红素葡萄糖醛酸酯形成速率的结果是相同的。然而,后一种技术的灵敏度比放射分析低约10倍。