title: Plasma arteriovenous cGMP difference as a useful indicator of nitrate tolerance in patients with heart failure.
abstract: BACKGROUND
  The present study was performed to evaluate the effects of nitroglycerin (GTN) on plasma arteriovenous cGMP production and to compare its hemodynamic effects in patients with congestive heart failure (CHF). We also estimated the potential clinical value of plasma arteriovenous cGMP production as an indicator of nitrate tolerance.
  
  
  RESULTS
  Plasma arterial and venous cGMP levels, atrial natriuretic peptide level, and hemodynamic parameters were measured before and after GTN infusion in 14 patients with CHF. Although the plasma levels of arterial cGMP and atrial natriuretic peptide decreased immediately after GTN, the plasma level of venous cGMP did not change. GTN infusion caused a dose-dependent increase in plasma arteriovenous cGMP production, and there was a positive correlation between the decrease of pulmonary capillary wedge pressure and the increase of plasma arteriovenous cGMP production immediately after GTN. Hemodynamic tolerance was observed after both 12 and 24 hours, when plasma arteriovenous GMP production was also attenuated.
  
  
  CONCLUSIONS
  These findings indicate that the plasma arteriovenous cGMP difference is a clinical indicator of vasodilatory action of GTN and a useful indicator of nitrate tolerance in patients with CHF.
authors.affiliation: First Department of Internal Medicine, Shiga University of Medical Science, Otsu, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Tsutamoto
authors.forename: M
authors.initials: M
authors.lastname: Kinoshita
authors.forename: Y
authors.initials: Y
authors.lastname: Ohbayashi
authors.forename: A
authors.initials: A
authors.lastname: Wada
authors.forename: Y
authors.initials: Y
authors.lastname: Maeda
authors.forename: T
authors.initials: T
authors.lastname: Adachi
mesh_terms: D009320:Atrial Natriuretic Factor / Q000097:blood; D002216:Captopril / Q000494:pharmacology; D006152:Cyclic GMP / Q000096:biosynthesis / Q000097:blood*; D004305:Dose-Response Relationship, Drug; D004361:Drug Tolerance; D005260:Female; D006333:Heart Failure / Q000097:blood / Q000188:drug therapy* / Q000503:physiopathology; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D005996:Nitroglycerin / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D011669:Pulmonary Wedge Pressure / Q000187:drug effects
chemical_list: D009320:Atrial Natriuretic Factor; D002216:Captopril; D005996:Nitroglycerin; D006152:Cyclic GMP