title: The effect of sildenafil on right ventricular remodeling in a rat model of monocrotaline-induced right ventricular failure.
abstract: OBJECTIVE
  Pulmonary arterial hypertension (PAH) leads to right ventricular failure (RVF) as well as an increase in pulmonary vascular resistance. Our purpose was to study the effect of sildenafil on right ventricular remodeling in a rat model of monocrotaline (MCT)-induced RVF.
  
  
  METHODS
  The rats were distributed randomly into 3 groups. The control (C) group, the monocrotaline (M) group (MCT 60 mg/kg) and the sildenafil (S) group (MCT 60 mg/kg+ sildenafil 30 mg/kg/day for 28 days). Masson Trichrome staining was used for heart tissues. Western blot analysis and immunohistochemical staining were performed.
  
  
  RESULTS
  The mean right ventricular pressure (RVP) was significantly lower in the S group at weeks 1, 2, and 4. The number of intra-acinar arteries and the medial wall thickness of the pulmonary arterioles significantly lessened in the S group at week 4. The collagen content also decreased in heart tissues in the S group at week 4. Protein expression levels of B-cell lymphoma-2 (Bcl-2)-associated X, caspase-3, Bcl-2, interleukin (IL)-6, matrix metalloproteinase (MMP)-2, endothelial nitric oxide synthase (eNOS), endothelin (ET)-1 and ET receptor A (ERA) in lung tissues greatly decreased in the S group at week 4 according to immunohistochemical staining. According to Western blotting, protein expression levels of troponin I, brain natriuretic peptide, caspase-3, Bcl-2, tumor necrosis factor-α, IL-6, MMP-2, eNOS, ET-1, and ERA in heart tissues greatly diminished in the S group at week 4.
  
  
  CONCLUSIONS
  Sildenafil alleviated right ventricular hypertrophy and mean RVP. These data suggest that sildenafil improves right ventricular function.
authors.affiliation: Department of Pediatrics, Ewha Womans University School of Medicine, Seoul, Korea.
authors.forename: Hyun Kyung
authors.initials: HK
authors.lastname: Bae
authors.affiliation: Department of Pediatrics, Ewha Womans University School of Medicine, Seoul, Korea.
authors.forename: Hyeryon
authors.initials: H
authors.lastname: Lee
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, Ewha Womans University School of Medicine, Seoul, Korea.
authors.forename: Kwan Chang
authors.initials: KC
authors.lastname: Kim
authors.affiliation: Department of Pediatrics, Ewha Womans University School of Medicine, Seoul, Korea.
authors.forename: Young Mi
authors.initials: YM
authors.lastname: Hong
keywords: Gene expression; Pulmonary hypertension; Sildenafil citrate