title: Very short cycles of postconditioning have no protective effect against reperfusion injury. Experimental study in rats.
abstract: BACKGROUND
  Ischemic postconditioning has been recognized as effective in the prevention of reperfusion injury in situations of ischemia and reperfusion in various organs and tissues. However, it remains unclear what would be the best way to accomplish it, since studies show great variation in the method of their application.
  
  
  OBJECTIVE
  To assess the protective effect of ischemic postconditioning on ischemia and reperfusion in rats undergoing five alternating cycles of reperfusion and ischemia of 30 seconds each one.
  
  
  METHODS
  We studied 25 Wistar rats distributed in three groups: group A (10 rats), which underwent mesenteric ischemia (30 minutes) and reperfusion (60 minutes); Group B (10 rats), undergoing ischemia (30 minutes) and reperfusion (60 minutes), intercalated by postconditioning (5 alternating cycles of reperfusion and ischemia of 30 seconds each one); and group C - SHAM (5 rats), undergoing only laparotomy and manipulation of mesenteric artery. All animals underwent resection of an ileum segment for histological analysis.
  
  
  RESULTS
  The mean lesions degree according to Chiu et al. were: group A, 2.77, group B, 2.67 and group C, 0.12. There was no difference between groups A and B (P>0.05).
  
  
  CONCLUSIONS
  Ischemic postconditioning was not able to minimize or prevent the intestinal tissue injury in rats undergoing ischemia and reperfusion process when used five cycles lasting 30 seconds each one.
authors.affiliation: Faculdade de Medicina, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, Brazil.
authors.forename: Ricardo Kenithi
authors.initials: RK
authors.lastname: Nakamura
authors.affiliation: Faculdade de Medicina, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, Brazil.
authors.forename: Carlos Henrique Marques dos
authors.initials: CH
authors.lastname: Santos
authors.affiliation: Pathology Devision, Universidade Federal de São Paulo, São Paulo, SP, Brazil.
authors.forename: Luciana Nakao Odashiro
authors.initials: LN
authors.lastname: Miiji
authors.affiliation: Faculdade de Medicina, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, Brazil.
authors.forename: Mariana Sousa
authors.initials: MS
authors.lastname: Arakaki
authors.affiliation: Faculdade de Medicina, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, Brazil.
authors.forename: Cristiane Midori
authors.initials: CM
authors.lastname: Maedo
authors.affiliation: Faculdade de Medicina, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, Brazil.
authors.forename: Maurício
authors.initials: M
authors.lastname: Érnica Filho
authors.affiliation: Faculdade de Medicina, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, Brazil.
authors.forename: Pedro Carvalho
authors.initials: PC
authors.lastname: Cassino
authors.affiliation: Faculdade de Medicina, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, Brazil.
authors.forename: Elenir Rose Jardim Cury
authors.initials: ER
authors.lastname: Pontes
mesh_terms: D000818:Animals; D007413:Intestinal Mucosa / Q000098:blood supply / Q000473:pathology; D007422:Intestines / Q000098:blood supply* / Q000473:pathology; D057775:Ischemic Postconditioning / Q000379:methods*; D008297:Male; D008638:Mesenteric Arteries / Q000473:pathology; D065666:Mesenteric Ischemia / Q000517:prevention & control*; D008641:Mesenteric Vascular Occlusion / Q000473:pathology; D023421:Models, Animal; D017208:Rats, Wistar; D015427:Reperfusion Injury / Q000517:prevention & control*; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D013997:Time Factors