title: Heart injury following intestinal ischemia reperfusion in rats is attenuated by association of ischemic preconditioning and adenosine.
abstract: OBJECTIVE
  To investigate the effect of ischemic preconditioning (IPC) and adenosine as strategies to protect cardiac injury caused by intestinal IR in rats, based on increasing in adenosine bioavailability and improvement of cell energy state by IPC.
  
  
  METHODS
  Male Wistar rats were submitted to 60 minutes of intestinal ischemia and 120 minutes of reperfusion. Intravenous injections of saline or Adenosine (AD) was administered five minutes before ischemia, five minutes before reperfusion and after 55 minutes reperfusion. Cardiac samples were obtained, fixed in formalin solution, embedded in paraffin, and sections of 5 μm were stained by hematoxylin-eosin. Histological analysis of myocardium was performed according occurrence of necrosis signs: piknosis, band contraction, eosinophilic cytoplasm, karyorrhexis and vacuolization (score - zero to 5).
  
  
  RESULTS
  The groups submitted to ischemia alone (I=4.0), and reperfusion (IR=4.5) showed highest level of lesion compared to the others (I+IPC=3.3, IR+IPC=3.6, I+AD=3.0, IR+AD=3.8). The most interesting result was association of IPC and AD in IR model (IR+IPC+AD=1.2, p=0.002), showing preservation of the heart tissue, with fibers showing typical cross-striations and nuclei characteristics. Rare and small areas of tissue necrosis was observed and suggestion of capillaries congestion.
  
  
  CONCLUSIONS
  Intestinal ischemia reperfusion promotes cardiac tissue injury. Ischemic preconditioning in association with adenosine is an efficient strategy to protect the heart against ischemia and reperfusion injury.
authors.affiliation: ABC Medical School, Santo André, SP, Brazil.
authors.forename: Micaela Frasson
authors.initials: MF
authors.lastname: Montero
authors.affiliation: Federal University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Rafael
authors.initials: R
authors.lastname: Saurim
authors.affiliation: Federal University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Wesley Guedes Sava
authors.initials: WG
authors.lastname: Bonservizi
authors.affiliation: Faculty of Medicine, São Paulo University, Sao Paulo, Brazil.
authors.forename: Marcia Kiyomi
authors.initials: MK
authors.lastname: Koike
authors.affiliation: Department of Surgery, UNIFESP, Sao Paulo, Brazil.
authors.forename: Murched Omar
authors.initials: MO
authors.lastname: Taha
mesh_terms: D000241:Adenosine / Q000494:pharmacology*; D000818:Animals; D006335:Heart Injuries / Q000473:pathology / Q000517:prevention & control*; D007422:Intestines / Q000098:blood supply*; D019194:Ischemic Preconditioning / Q000379:methods*; D008297:Male; D058906:Purinergic P1 Receptor Agonists / Q000494:pharmacology*; D011897:Random Allocation; D017208:Rats, Wistar; D015427:Reperfusion Injury / Q000628:therapy*; D015203:Reproducibility of Results; D012965:Sodium Chloride / Q000494:pharmacology; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D058906:Purinergic P1 Receptor Agonists; D012965:Sodium Chloride; D000241:Adenosine