title: Gene expression of endothelin receptors in replaced rheumatic mitral stenotic valves.
abstract: OBJECTIVE
  Rheumatic fever is a highly prevalent disease in Brazil, and it poses a major public health problem. It is the leading cause of acquired heart disease in childhood and adolescence. The aim of this study was to evaluate the gene expression of ET-3 and its receptors, in replaced rheumatic mitral valves.
  
  
  METHODS
  We studied the gene expression of endothelin-3 (ET-3) and its receptors, endothelin receptor A and endothelin receptor B (ETr-A and ETr-B), in the rheumatic mitral valves of 17 patients who underwent valve replacement surgery. The samples also underwent a histological analysis.
  
  
  RESULTS
  Our data showed that almost all patients, regardless of individual characteristics such as gender or age, expressed the endothelin receptor genes, but did not express the genes for ET-3. In quantitative analysis, the ETr-A/GAPDH mean ratio was 33.04 ± 18.09%; while the ETr-B/GAPDH mean ratio was 114.58 ± 42.30%. Regarding histopathological individual features, the frequency of fibrosis is 100%, 88.23% of mononuclear infiltrate, 52.94% of neovascularization, 58.82% of calcification and absence of ossification.
  
  
  CONCLUSIONS
  The presence of receptors ETr-A and ETr-B in rheumatic mitral valves suggests its interaction with the system of circulating endothelins, particularly ETr-B (known for acting in the removal of excess endothelin) detected in a greater proportion, which could explain the lack of expression of endothelin in rheumatic mitral valve, process to be elucidated.
authors.affiliation: Laboratory of Molecular Anatomy, Department of Morphology, Biological and Health Science Center, Sergipe Federal University, São Cristóvão, SE, Brazil. sydneyleao@hotmail.com
authors.forename: Sydney Correia
authors.initials: SC
authors.lastname: Leão
authors.forename: Fernanda Maria Silveira
authors.initials: FM
authors.lastname: Souto
authors.forename: Ricardo Vieira da
authors.initials: RV
authors.lastname: Costa
authors.forename: Thaisa de Fatima Almeida
authors.initials: Tde F
authors.lastname: Rocha
authors.forename: Yolanda Galindo
authors.initials: YG
authors.lastname: Pacheco
authors.forename: Tania Maria de Andrade
authors.initials: TM
authors.lastname: Rodrigues
mesh_terms: D000328:Adult; D019334:Endothelin-3 / Q000235:genetics* / Q000378:metabolism; D005260:Female; D015870:Gene Expression / Q000235:genetics*; D019918:Heart Valve Prosthesis Implantation; D006801:Humans; D008297:Male; D008946:Mitral Valve Stenosis / Q000235:genetics* / Q000601:surgery; D044022:Receptor, Endothelin A / Q000235:genetics* / Q000378:metabolism; D044023:Receptor, Endothelin B / Q000235:genetics* / Q000378:metabolism; D012214:Rheumatic Heart Disease / Q000235:genetics* / Q000378:metabolism / Q000601:surgery
chemical_list: D019334:Endothelin-3; D044022:Receptor, Endothelin A; D044023:Receptor, Endothelin B