Immunoradiometric assay for the N-terminal fragment of proatrial natriuretic peptide in human plasma

• Published in: Clinical chemistry (Baltimore, Md.) Vol. 44; no. 5; pp. 1008 - 1013
• Main Authors: NUMATA, Y, DOHI, K, YOSHIMURA, M, ITOH, H, MUKOYAMA, M, YASUE, H, NAKAO, K, FURUKAWA, A, KIKUOKA, S, ASADA, H, FUKUNAGA, T, TANIGUCHI, Y, SASAKURA, K, TSUJI, T, INOUYE, K
• Format: Conference Proceeding Journal Article
• Language: English
• Published: Washington, DC American Association for Clinical Chemistry 01-05-1998
• Subjects: Aminoacids, peptides. Hormones. Neuropeptides; Analytical, structural and metabolic biochemistry; Antibodies, Monoclonal - immunology; Atrial Natriuretic Factor - blood; Atrial Natriuretic Factor - immunology; Biological and medical sciences; Biomarkers - blood; Chromatography, Gel; Cross Reactions; Drug Stability; Edetic Acid; Epitopes - immunology; Fundamental and applied biological sciences. Psychology; Heart Failure - blood; Hemolysis; Humans; Immunoradiometric Assay - methods; Protein Precursors - blood; Protein Precursors - immunology; Proteins; Reproducibility of Results; Sensitivity and Specificity; Human; Heart failure; Biological fluid; Peptide hormone; Biological marker; Cardiovascular disease; Atrial natriuretic peptide; Normal; N terminal peptide; Prohormone; Blood plasma; Natriuretic hormone; Peptide fragment; Heart disease; Radioimmunoassay; Clinical biology; Comparative study; Quantitative analysis
• ISSN: 0009-9147; 1530-8561

Recently, the N-terminal fragment of proatrial natriuretic peptide (N-terminal proANP) has been proposed as a marker of chronic congestive heart failure. In this study, we established a two-step immunoradiometric assay using monoclonal antibodies and synthetic N-terminal proANP (1-67) as a standard. It allows us to measure plasma N-terminal proANP in only 4 h without prior extraction. The detection limit of this assay was 15 pmol/L for a 100 microL sample of plasma. Within-run CVs ranged from 1.7% to 2.9% and between-run CVs ranged from 4.2% to 5.1%. The dilution curves of plasma samples showed good linearity and analytical recovery was 89-104%. The mean (+/-SD) N-terminal proANP in plasma of 33 healthy subjects was 188 (+/-71) pmol/L and 1030 (+/-411) pmol/L in 25 patients with heart failure. Our immunoradiometric assay is rapid and precise enough for routine determination of N-terminal proANP in human plasma.