title: Experimental model of Achilles tendon injury in rats.
abstract: OBJECTIVE
  To describe an effective experimental model to study the Achilles tendon healing.
  
  
  METHODS
  Forty male Rattus norvegicus albinus, Wistar lineage adult male weighing 250 to 300g were used for this experiment and thirty were surgically submitted to bilateral partial transverse section of the Achilles tendon. The right tendon was treated with radio waves (RF) whereas the left tendon served as control. On the third postoperative day, the rats were divided into four experimental groups consisting of ten rats each which were treated with monopolar RF adjusted to 650 kHz and 2w, for two minutes twice a week and a group of normal animals without any intervention, until they were sacrificed on the 7th, 14th and 28th days, respectively. Tendons were weighed and collagen quantification was evaluated by hydroxyprolin content.
  
  
  RESULTS
  Significant reduction in collagen content on day 7, 14 and 28 was related to control experiment to normal tendon (7 days, p<0.01; 14 e 28 days, p<0.05).
  
  
  CONCLUSIONS
  The experimental model has been effective and available to be used to study Achilles tendon healing.
authors: Department of Surgery, Faculty of Medicine, University of Sao Paulo, Brazil.
authors: Flavia Emi
authors: FE
authors: Akamatsu
authors: FM, USP, Sao Paulo, SP, Brazil.
authors: Samir Omar
authors: SO
authors: Saleh
authors: Department of Internal Medicine, FM, USP, Sao Paulo, SP, Brazil.
authors: Walcy Rosolia
authors: WR
authors: Teodoro
authors: FM, USP, Sao Paulo, SP, Brazil.
authors: Alexandre Queiroz da
authors: AQ
authors: Silva
authors: Medical School, Sao Francisco University, Bragança Paulista, SP, Brazil.
authors: Carlos Augusto Real
authors: CA
authors: Martinez
authors: Center for Teaching and Research in Surgery, FM, USP, Sao Paulo, SP, Brazil.
authors: Ricardo Jordão
authors: RJ
authors: Duarte
authors: Department of Surgery, FM, USP, Sao Paulo, SP, Brazil.
authors: Mauro Figueiredo Carvalho de
authors: MF
authors: Andrade
authors: Department of Surgery, FM, USP, Sao Paulo, SP, Brazil.
authors: Alfredo Luiz
authors: AL
authors: Jacomo
mesh_terms: D000125:Achilles Tendon / Q000293:injuries*; D000818:Animals; D003094:Collagen / Q000032:analysis; D004195:Disease Models, Animal; D008297:Male; D017208:Rats, Wistar; D012016:Reference Values; D015203:Reproducibility of Results; D013708:Tendon Injuries / Q000503:physiopathology*; D013997:Time Factors; D014945:Wound Healing / Q000502:physiology*
chemical_list: D003094:Collagen