2004 Volume 33 Issue 3-4 Pages 187-191
Brain natriuretic peptide (BNP) is known to be degraded during the preservation of blood samples. We investigated the stability of BNP in the blood preserved under various conditions. The most effective protection against BNP degradation was obtained by preserving blood samples as plasma with EDTA and aprotinin at 4°C. Under this condition, mostly more than 90% of BNP was detected after 6 hours. The omission of aprotinin weakened the protective effect. In serum, BNP was rapidly degraded but stabilized by EDTA and aprotinin at 4°C. A “Protease inhibitor cocktail” had the effect similar to that of EDTA and aprotinin. Leupeptin, a component in this cocktail, was the most effective agent. These observations suggested that non-frozen blood samples for BNP measurement could be preserved with EDTA and aprotinin at 4°C for several hours.
