title: C-type natriuretic peptide plasma levels increase in patients with chronic heart failure as a function of clinical severity.
abstract: BACKGROUND
  [corrected] C-type natriuretic peptide (CNP), secreted by the endothelium and the heart, is structurally related to atrial and brain natriuretic peptides, but its clinical significance in chronic heart failure (CHF) is controversial.
  
  
  OBJECTIVE
  To investigate the role of CNP in CHF, plasma CNP levels were determined in a prospective series of 133 patients with CHF (age 64 +/- 1 years, left ventricular ejection fraction (EF), 31.5 +/- 0.7%, mean +/-S.E.M.) and in 21 age-matched healthy subjects.
  
  
  RESULTS
  CNP was measured by a radioimmunoassay (sensitivity: 0.41+/-0.009 pg/tube) after a preliminary solid-phase extraction. Plasma level of CNP in healthy subjects was 2.7 +/- 0.2 pg/ml and significantly increased in CHF, as a function of clinical severity: 4.9 +/- 0.7 pg/ml in NYHA class I; 7.0 +/- 0.4 pg/ml in class II (p < 0.001 vs. controls); 9.6 +/- 0.7 pg/ml in class III (p < 0.001 vs. controls and class I and II), and 11.8 +/- 2.0 pg/ml in class IV (p < 0.001 vs. controls, class I and II; Fisher's test after ANOVA). A significant relation was also found between CNP plasma levels and EF (R = 0.40, p < 0.001).
  
  
  CONCLUSIONS
  Plasma CNP elevation is related to clinical and functional disease severity. These findings suggest a pathophysiological role for this peptide that, for its vasorelaxing activity, could influence the endothelial vasomotor response in CHF.
authors.affiliation: Institute of Clinical Physiology, National Research Council, Pisa, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Del Ry
authors.forename: Claudio
authors.initials: C
authors.lastname: Passino
authors.forename: Maristella
authors.initials: M
authors.lastname: Maltinti
authors.forename: Michele
authors.initials: M
authors.lastname: Emdin
authors.forename: Daniela
authors.initials: D
authors.lastname: Giannessi
mesh_terms: D015415:Biomarkers / Q000097:blood; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000097:blood* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D020098:Natriuretic Peptide, C-Type / Q000097:blood*; D011446:Prospective Studies; D011863:Radioimmunoassay; D012720:Severity of Illness Index; D013318:Stroke Volume
chemical_list: D015415:Biomarkers; D020098:Natriuretic Peptide, C-Type