title: Prior exercise training does not prevent acute cardiac alterations after myocardial infarction in female rats.
abstract: OBJECTIVE
  This study aimed to investigate whether previous exercise training could prevent or attenuate acute cardiac alterations after myocardial infarction.
  
  
  METHODS
  Female rats were submitted to swim training (1 h/day; 5 days/week) or allowed to remain sedentary for 8 weeks. Afterwards, they were randomly assigned to left coronary artery occlusion or sham surgery. After this procedure, the rats remained sedentary for one week until euthanasia. Cardiac structural and functional analyses were performed using Doppler echocardiography. The rats that had a moderate or large infarct size were included in the evaluations. The data (mean ± SEM) were analyzed using a two-way ANOVA model followed by Tukey's post-hoc test.
  
  
  RESULTS
  After the surgery, no significant difference between the exercise and sedentary groups was observed in the left ventricular infarct sizes (34.58 ± 3.04 vs. 37.59 ± 3.07). In another group of rats evaluated with Evans blue 1 h after myocardial infarction, no siginificant difference in the area at risk was observed between the exercised and sedentary rats (49.73 ± 1.52 vs. 45.48 ± 3.49). The changes in the left ventricular fractional areas for the exercised and sedentary myocardial infarction groups (36 ± 2% and 39 ± 3%, respectively) were smaller than those for the exercise sham surgery (ES, 67 ± 1%) and sedentary sham surgery (SS, 69 ± 2%) groups. The E/A was higher in the sedentary myocardial infarction (4.4 ± 0.3) and exercised myocardial infarction (5.5 ± 0.3) rats than in the SS (2.4 ± 0.1) and ES (2.2 ± 0.1) rats.
  
  
  CONCLUSIONS
  Previous swim training of female rats does not attenuate systolic and diastolic function alterations after myocardial infarction induced by left coronary artery occlusion, suggesting that cardioprotection cannot be provided by exercise training in this experimental model.
authors.affiliation: Department of Medicine, Cardiology division. Universidade Federal de São Paulo - Escola Paulista de Medicina, São Paulo, SP, Brazil. eduveiga@fcr.epm.br
authors.forename: Eduardo C A
authors.initials: EC
authors.lastname: Veiga
authors.forename: Ednei L
authors.initials: EL
authors.lastname: Antonio
authors.forename: Danilo S
authors.initials: DS
authors.lastname: Bocalini
authors.forename: Neif
authors.initials: N
authors.lastname: Murad
authors.forename: Luiz C
authors.initials: LC
authors.lastname: Abreu
authors.forename: Paulo J F
authors.initials: PJ
authors.lastname: Tucci
authors.forename: Monica A
authors.initials: MA
authors.lastname: Sato
mesh_terms: D000818:Animals; D023921:Coronary Stenosis / Q000503:physiopathology; D005260:Female; D009203:Myocardial Infarction / Q000473:pathology / Q000503:physiopathology*; D010805:Physical Conditioning, Animal / Q000502:physiology*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D013550:Swimming / Q000502:physiology*; D018754:Ventricular Dysfunction / Q000503:physiopathology*