title: Decreased renal sympathetic activity in response to cardiac unloading with nitroglycerin in patients with heart failure.
abstract: OBJECTIVE
  To examine changes in renal sympathetic outflow in response to cardiac unloading with nitroglycerin (GTN) in patients with chronic heart failure (CHF) and healthy subjects (HS).
  
  
  RESULTS
  Renal (RNAsp) and total body (TBNAsp) noradrenaline (NA) spillover were measured with radiotracer methods in 16 patients with CHF (50+/-3 years, LVEF 20+/-1%) and nine HS (57+/-2 years) during right heart and renal vein catheterisation. Low dose GTN decreased mean pulmonary artery pressure (PAm: CHF -7+/-2 mm Hg, HS -4+/-1 mm Hg, p<0.05 vs. baseline) but not mean arterial pressure (MAP: CHF -2+/-1 mm Hg, HS -2+/-1 mm Hg) and did not affect RNAsp in any of the study groups. High dose GTN lowered MAP (CHF -12+/-1 mm Hg, HS -12+/-2 mm Hg, p<0.05 vs. baseline) and PAm (CHF -13+/-2 mm Hg, HS -5+/-1 mm Hg, p<0.05 vs. baseline) and was accompanied by a significant reduction in RNAsp only in CHF (1.3+/-0.1 nmol/min baseline to 0.9+/-0.2 nmol/min, p<0.05), whereas RNAsp in HS remained unchanged.
  
  
  CONCLUSIONS
  In spite of a reduction in both arterial pressure and cardiac filling pressures, renal sympathetic activity decreased in CHF and did not increase in HS. These findings suggest that the altered loading conditions resulting from high-dose GTN infusion have renal sympathoinhibitory effects.
authors.affiliation: Department of Cardiology, The Cardiovascular Institute, Sahlgrenska University Hospital, S-413 45 Göteborg, Sweden. magnus.petersson@wlab.gu.se
authors.forename: Magnus
authors.initials: M
authors.lastname: Petersson
authors.forename: Peter
authors.initials: P
authors.lastname: Friberg
authors.forename: Gavin
authors.initials: G
authors.lastname: Lambert
authors.forename: Bengt
authors.initials: B
authors.lastname: Rundqvist
mesh_terms: D000704:Analysis of Variance; D006328:Cardiac Catheterization; D016022:Case-Control Studies; D004305:Dose-Response Relationship, Drug; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000175:diagnosis* / Q000188:drug therapy*; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D007262:Infusions, Intravenous; D007668:Kidney / Q000000981:diagnostic imaging* / Q000187:drug effects; D007677:Kidney Function Tests; D008297:Male; D008875:Middle Aged; D005996:Nitroglycerin / Q000493:pharmacokinetics* / Q000627:therapeutic use; D011336:Probability; D011877:Radionuclide Imaging; D012016:Reference Values; D012079:Renal Circulation / Q000187:drug effects / Q000502:physiology; D018570:Risk Assessment; D012720:Severity of Illness Index; D018709:Statistics, Nonparametric; D013564:Sympathetic Nervous System / Q000187:drug effects*; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis / Q000188:drug therapy
chemical_list: D005996:Nitroglycerin