title: Role of aldosterone on lung structural remodelling and right ventricular function in congestive heart failure.
abstract: BACKGROUND
  The mechanisms of benefit of mineralocorticoid receptors antagonists in congestive heart failure (CHF) are still debated. We hypothesized that aldosterone contributes to pulmonary remodelling and right ventricular (RV) dysfunction associated with CHF by stimulation of lung myofibroblasts (MYFs) proliferation.
  
  
  METHODS
  Rats with moderate to large myocardial infarcts (MI) and CHF were studied. Two weeks after MI, spironolactone 100 mg/kg/day (n = 21) or no treatment (n = 24) were given for 3 weeks and compared to sham (n = 8).
  
  
  RESULTS
  Infarct size was similar by ultrasound and pathologic measures in both MI groups.The MI-untreated group developed important lung remodelling with nearly doubling of dry lung weight (p < 0.01), reduced left ventricular (LV) fractional shortening (16 ± 2% vs. 53 ± 1%; mean ± SEM, p < 0.0001), pulmonary hypertension (RV systolic pressure: 40 ± 3 mmHg vs. 27 ± 1 mmHg, p < 0.01) and RV hypertrophy (RV/(LV + septum): 38 ± 3% vs. 24 ± 1%, p < 0.05). Spironolactone had no effect on these parameters and did not improve LV or RV performance (tricuspid annular plane systolic excursion and RV myocardial performance index) measured by echocardiography. CHF induced a restrictive respiratory syndrome with histological lung fibrosis: this was also unaffected by spironolactone. Finally, isolated lung MYFs did not proliferate after exposure to aldosterone.
  
  
  CONCLUSIONS
  Aldosterone does not significantly contribute to pulmonary remodelling and RV dysfunction associated with CHF. Other mechanisms are responsible for the beneficial effects of spironolactone in CHF.
authors.affiliation: Research Center, Montreal Heart Institute/Université de Montréal, 5000 Bélanger Street, Montreal, Quebec, H1T 1C8, Canada.
authors.forename: Andreanne
authors.initials: A
authors.lastname: Chabot
authors.forename: Bao Hua
authors.initials: BH
authors.lastname: Jiang
authors.forename: Yanfen
authors.initials: Y
authors.lastname: Shi
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Tardif
authors.forename: Jocelyn
authors.initials: J
authors.lastname: Dupuis
mesh_terms: D000450:Aldosterone / Q000502:physiology*; D000818:Animals; D049109:Cell Proliferation / Q000187:drug effects*; D004452:Echocardiography; D006333:Heart Failure / Q000150:complications / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006976:Hypertension, Pulmonary / Q000473:pathology; D017380:Hypertrophy, Right Ventricular / Q000473:pathology; D008168:Lung / Q000187:drug effects / Q000502:physiology*; D008297:Male; D000451:Mineralocorticoid Receptor Antagonists / Q000494:pharmacology*; D009203:Myocardial Infarction / Q000150:complications; D009206:Myocardium / Q000473:pathology; D058628:Myofibroblasts / Q000187:drug effects*; D051381:Rats; D017208:Rats, Wistar; D013148:Spironolactone / Q000494:pharmacology*; D016278:Ventricular Function, Right / Q000187:drug effects / Q000502:physiology*; D020257:Ventricular Remodeling / Q000187:drug effects / Q000502:physiology
chemical_list: D000451:Mineralocorticoid Receptor Antagonists; D013148:Spironolactone; D000450:Aldosterone