Identification of amino-terminal pro-C-type natriuretic peptide in human plasma

Biochem Biophys Res Commun. 2001 Aug 24;286(3):513-7. doi: 10.1006/bbrc.2001.5419.


We report the first identification of a circulating peptide from the amino-terminal end of proCNP. A specific radioimmunoassay was established based on antisera to the synthetic peptide proCNP(1-15). Extracts of plasma, drawn from patients with congestive heart failure or from sheep with experimental heart failure, were subjected to size exclusion and reverse-phase high-pressure liquid chromatography (HPLC) coupled to radioimmunoassay (RIA). These studies revealed the presence of an immunoreactive peptide with a molecular weight (M(r) approximately 5 kDa) similar to that expected for NT-proCNP(1-50), a potential fragment released during processing of pro(CNP). The same material was isolated from extracts of homogenized ovine pituitary, a tissue known to be a relatively enriched source of CNP. Plasma NT-proCNP levels in 22 patients with congestive heart failure (9.7 +/- 0.5 pmol/L, mean +/- SEM, range 5.4-13.7 pmol/L) were raised (P = 0.003) compared to those in 16 healthy volunteers (7.4 +/- 0.3 pmol/L, range 5.7-10.7 pmol/L) and were higher than levels reported for CNP in similar subjects. This first identification of circulating NT-proCNP opens the possibility of studying the factors regulating CNP production and metabolism in vivo.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Chromatography, High Pressure Liquid
  • Female
  • Heart Failure / blood
  • Humans
  • Male
  • Models, Chemical
  • Natriuretic Peptide, C-Type / blood*
  • Natriuretic Peptide, C-Type / chemistry*
  • Natriuretic Peptide, C-Type / immunology
  • Peptides / analysis
  • Protein Precursors / blood
  • Protein Precursors / chemistry
  • Protein Precursors / immunology
  • Radioimmunoassay / methods
  • Sheep
  • Tissue Extracts / chemistry


  • Peptides
  • Protein Precursors
  • Tissue Extracts
  • Natriuretic Peptide, C-Type