Richards A M, Tonolo G, McIntyre G D, Leckie B J, Robertson J I
J Hypertens. 1987 Apr;5(2):227-36. doi: 10.1097/00004872-198704000-00015.
Plasma atrial natriuretic peptide (ANP) concentrations were measured by both direct radio-immunoassay and with pre-extraction of the peptide from plasma using C18 reverse phase columns. Peptide concentrations were measured in normal subjects (including a group of eight volunteers who received an intravenous infusion of 0.9% NaCl solution), patients with renal failure (including a group with end-stage disease undergoing renal dialysis) and patients with a spectrum of cardiac dysfunction. The overall correlation of results from direct and extracted assay methods was good. However, absolute values from extracted assays were significantly lower than from parallel direct assays. This discrepancy was due to interference from platelets and from another, as yet unidentified, plasma component demonstrated by gel filtration experiments. Extraction of the peptide from plasma by C18 columns largely eliminated these sources of interference and was particularly important for accurate measurement of peptide concentrations within the normal range. Plasma peptide concentrations were elevated in cardiac and renal failure, fell with renal dialysis and rose in normal subjects challenged with an intravenous isotonic fluid load. These findings suggest that ANP participates in the regulation of body fluid volumes and arterial pressure.
采用直接放射免疫分析法以及使用C18反相柱从血浆中预先提取肽段的方法来测定血浆心钠素（ANP）浓度。在正常受试者（包括一组接受0.9%氯化钠溶液静脉输注的8名志愿者）、肾衰竭患者（包括一组接受肾脏透析的终末期疾病患者）以及一系列心脏功能障碍患者中测量肽段浓度。直接测定法和提取测定法的结果总体相关性良好。然而，提取测定法的绝对值明显低于平行直接测定法。这种差异是由于血小板以及凝胶过滤实验所显示的另一种尚未确定的血浆成分的干扰所致。通过C18柱从血浆中提取肽段在很大程度上消除了这些干扰源，对于准确测量正常范围内的肽段浓度尤为重要。心力衰竭和肾衰竭患者的血浆肽段浓度升高，肾脏透析后下降，而接受静脉等渗液体负荷刺激的正常受试者的血浆肽段浓度升高。这些发现表明，心钠素参与了体液容量和动脉血压的调节。
