Harwood S, Little J A, Gallacher G, Perrett D, Edwards R, Dawnay A
Department of Clinical Biochemistry, London, UK.
Clin Chem. 1997 May;43(5):715-22.
Widespread evidence supports the existence of an endogenous digitalis-like compound in mammals. We report here the development of a novel enzyme immunoassay for ouabain that, in conjunction with a detailed HPLC study, identifies a ouabain-like compound (OLC) in extracted human plasma. The assay is sensitive-minimum detection limit for OLC 37 pmol/L (11 pmol/L in plasma)-and has a working range (between-assay CV < 10%) of 180-10000 pmol/L (54-3000 pmol/L in plasma). Mean recoveries of ouabain added to plasma ranged from 90% to 100%, and plasma extracts diluted in parallel to the standard curve. Plasma OLC concentrations in 10 healthy volunteers averaged 92 pmol/L (range 55-168), assuming 100% cross-reactivity of OLC in the ouabain assay. HPLC analysis with two distinct chromatographic conditions demonstrated that endogenous human plasma OLC co-eluted with authentic ouabain. The enzyme immunoassay is rapid and easy to perform and will support further investigation of the nature of this controversial endogenous steroid.
大量证据支持哺乳动物体内存在一种内源性类洋地黄化合物。我们在此报告一种针对哇巴因的新型酶免疫测定法的开发，该方法结合详细的高效液相色谱研究，在提取的人血浆中鉴定出一种类哇巴因化合物（OLC）。该测定法灵敏——OLC的最低检测限为37 pmol/L（血浆中为11 pmol/L），工作范围（批间变异系数<10%）为180 - 10000 pmol/L（血浆中为54 - 3000 pmol/L）。添加到血浆中的哇巴因平均回收率在90%至100%之间，血浆提取物与标准曲线平行稀释。假设OLC在哇巴因测定法中的交叉反应率为100%，10名健康志愿者的血浆OLC浓度平均为92 pmol/L（范围为55 - 168）。在两种不同色谱条件下进行的高效液相色谱分析表明，内源性人血浆OLC与纯品哇巴因共洗脱。该酶免疫测定法快速且易于操作，将有助于对这种有争议的内源性类固醇的性质进行进一步研究。
