title: Growth factor expression after supraspinatus tear: a quantitative polymerase chain reaction (PCR) study in rats.
abstract: BACKGROUND
  The objective of this study was to evaluate the temporal expression pattern of three different growth factors (VEGF, IL-1β, and TGF-1β) in a supraspinatus tendon lesion in an animal model. The hypothesis of this study is that there are variations in the expression of these factors in the first 8 weeks after injury.
  
  
  METHODS
  A full thickness defect was made in the supraspinatus tendon of 40 rat shoulders. The animal were sacrificed at 0, 3, 7, 14 and 56 days after injury and three tissue samples were obtained: bone from the tendon footprint; the supraspinatus tendon stump, and a fragment of the myotendinous junction. After mRNA extraction, quantitative PCR analysis was performed, and the expression of three different growth factors were evaluated in each zone.
  
  
  RESULTS
  There was an increased expression of IL-1β during the first week after injury at all levels evaluated with a clear peak in the first day after injury. There was also a significant increase in TGF-1β expression levels all along the first week in the three zones. There were no variations in VEGF expression in the three zones along the 8 weeks.
  
  
  CONCLUSIONS
  IL-1β was expressed predominantly in the initial stages after injury; TGF initiated its expression after the initial phase since day three, whereas VEGF remained basically unchanged during the entire process.
authors.affiliation: Unidad de Hombro y Codo, Servicio de Traumatología y Cirugía Ortopédica, Hospital Universitario Ramón y Cajal, Madrid, Spain. drdiazheredia@gmail.com.
authors.forename: Jorge
authors.initials: J
authors.lastname: Díaz Heredia
authors.affiliation: Unidad de Hombro y Codo, Servicio de Traumatología y Cirugía Ortopédica, Hospital Universitario Ramón y Cajal, Madrid, Spain.
authors.forename: M A
authors.initials: MA
authors.lastname: Ruiz Iban
authors.affiliation: Servicio de Bioquímica-Investigación, Hospital Universitario Ramón y Cajal, IRYCIS, Madrid, Spain.|CIBER de Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, Madrid, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Martínez-Botas
authors.affiliation: Servicio de Traumatología y Cirugía Ortopédica, Fundación Jiménez Díaz, Madrid, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Valencia Mora
authors.affiliation: Servicio de Traumatología y Cirugía Ortopédica, Hospital Galdakao Usansolo, Galdakao, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Cuéllar Ayestaran
authors.affiliation: Servicio de Traumatología y Cirugía Ortopédica, Hospital MAZ, Zaragoza, Spain.
authors.forename: S
authors.initials: S
authors.lastname: Moros Marco
authors.affiliation: Unidad de Hombro y Codo, Servicio de Traumatología y Cirugía Ortopédica, Hospital Universitario Ramón y Cajal, Madrid, Spain.
authors.forename: R
authors.initials: R
authors.lastname: Ruiz Díaz
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005786:Gene Expression Regulation; D036341:Intercellular Signaling Peptides and Proteins / Q000096:biosynthesis / Q000235:genetics*; D008297:Male; D016133:Polymerase Chain Reaction; D012313:RNA / Q000235:genetics*; D051381:Rats; D017207:Rats, Sprague-Dawley; D017006:Rotator Cuff / Q000378:metabolism* / Q000473:pathology; D000070636:Rotator Cuff Injuries / Q000175:diagnosis / Q000235:genetics* / Q000378:metabolism
chemical_list: D036341:Intercellular Signaling Peptides and Proteins; D012313:RNA
keywords: Growth factor; IL-1β; Quantitative PCR; Supraspinatus tear; TGF-1β; VEGF