Lewis L K, Yandle T G, Lewis J G, Richards A M, Pidgeon G B, Kaaja R J, Nicholls M G
Department of Medicine, Christchurch Hospital, New Zealand.
Hypertension. 1994 Nov;24(5):549-55. doi: 10.1161/01.hyp.24.5.549.
An enzyme-linked immunosorbent assay is described for the measurement of ouabain in human plasma. This assay is specific for ouabain, strophanthidin, and ouabagenin, with other steroids, including digoxin and vasopressor hormones, exhibiting negligible cross-reactivity. Assay sensitivity was 0.06 nmol/L if 1 mL plasma was extracted and less than 0.005 nmol/L when 20 mL plasma was analyzed. Extracted plasma samples showed ouabainlike immunoreactivity that diluted in parallel with the ouabain standard curve. Repeated extraction and assay of single plasma samples, however, did not produce consistent results in the assay. Increased specificity was obtained by high-performance liquid chromatography of sample extracts before assay. When high-performance liquid chromatographic profiles of plasma spiked with ouabain standard or following bolus intravenous injections of ouabain into normal human volunteers were compared with profiles of unspiked plasma, there was no support for the immunoreactive material in the latter samples being ouabain. We propose that if ouabain is present in the human circulation, its concentration is less than 0.005 nmol/L.
本文描述了一种用于测定人血浆中哇巴因的酶联免疫吸附测定法。该测定法对哇巴因、毒毛旋花子苷元及哇巴因苷元具有特异性，而其他甾体类化合物，包括地高辛和血管升压素激素，交叉反应可忽略不计。若提取1 mL血浆，测定灵敏度为0.06 nmol/L；若分析20 mL血浆，灵敏度则小于0.005 nmol/L。提取的血浆样本显示出与哇巴因标准曲线呈平行稀释的类哇巴因免疫反应性。然而，对单个血浆样本进行重复提取和测定时，该测定法并未产生一致的结果。在测定前通过高效液相色谱法对样本提取物进行处理，可提高特异性。将添加了哇巴因标准品的血浆或正常人类志愿者静脉注射大剂量哇巴因后的血浆高效液相色谱图谱与未添加的血浆图谱进行比较时，未发现后者样本中的免疫反应性物质为哇巴因的证据。我们认为，若人循环系统中存在哇巴因，其浓度应小于0.005 nmol/L。
