Improved radioimmunoassay of atrial natriuretic peptide in plasma
Poiesi, C.; Rodella, A.; Mantero, G.; Cannella, G.; Ferrari, R.; Albertini, A.
Clinical Chemistry 35(7): 1431-1434
1989
ISSN/ISBN: 0009-9147 PMID: 2527094 Document Number: 344126
We describe a radioimmunoassay (RIA) for measurement of atrial natriuretic peptide (ANP), based on one-step incubation and a simplified extraction procedure. The extraction was performed on a "Supelclean LC 18" column, with 2-mL plasma samples. Use of a diiodinated tracer improved the sensitivity of the RIA method. The minimal detectable value was 5 ng/L. Simplification of the extraction procedure and simultaneous incubation of the reagents provide a method more suitable for routine standard assay of ANP than those currently available. Intra- and interassay CVs were 6% (n = 12) and 11% (n = 10), respectively. The mean concentration of ANP in plasma of 32 healthy volunteers was 33 (SEM 4) ng/L. The ANP values for plasma after one-step incubation correlated well with those determined by a commercial RIA kit: r = 0.971, slope = 1.099, intercept = 1.949 ng/L (n = 25).