title: EVALUATION OF THE EXTRACELLULAR MATRIX OF INJURED SUPRASPINATUS IN RATS.
abstract: OBJECTIVE
  To evaluate the evolution of injuries of the supraspinatus muscle by immunohistochemistry (IHC) and anatomopathological analysis in animal model (Wistar rats).
  
  
  METHODS
  Twenty-five Wistar rats were submitted to complete injury of the supraspinatus tendon, then subsequently sacrificed in groups of five animals at the following periods: immediately after the injury, 24h after the injury, 48h after, 30 days after and three months after the injury. All groups underwent histological and IHC analysis.
  
  
  RESULTS
  Regarding vascular proliferation and inflammatory infiltrate, we found a statistically significant difference between groups 1(control group) and 2 (24h after injury). IHC analysis showed that expression of vascular endothelial growth factor (VEGF) showed a statistically significant difference between groups 1 and 2, and collagen type 1 (Col-1) evaluation presented a statistically significant difference between groups 1 and 4.
  
  
  CONCLUSIONS
  We observed changes in the extracellular matrix components compatible with remodeling and healing. Remodeling is more intense 24h after injury. However, VEGF and Col-1 are substantially increased at 24h and 30 days after the injury, respectively. Level of Evidence I, Experimental Study.
authors.affiliation: Faculdade de Medicina do ABC, Santo André, SP, Brazil.
authors.forename: Luiz Henrique Oliveira
authors.initials: LH
authors.lastname: Almeida
authors.affiliation: Faculdade de Medicina do ABC, Santo André, SP, Brazil.
authors.forename: Roberto
authors.initials: R
authors.lastname: Ikemoto
authors.affiliation: Faculdade de Medicina do ABC, Santo André, SP, Brazil.
authors.forename: Ana Maria
authors.initials: AM
authors.lastname: Mader
authors.affiliation: Faculdade de Medicina do ABC, Santo André, SP, Brazil.
authors.forename: Maria Aparecida Silva
authors.initials: MA
authors.lastname: Pinhal
authors.affiliation: Faculdade de Medicina do ABC, Santo André, SP, Brazil.
authors.forename: Bruna
authors.initials: B
authors.lastname: Munhoz
authors.affiliation: Faculdade de Medicina do ABC, Santo André, SP, Brazil.
authors.forename: Joel
authors.initials: J
authors.lastname: Murachovsky
keywords: Collagen; Extracellular Matrix; Rats, Wistar