title: Optimal Duration of Coronary Ligation and Reperfusion for Reperfusion Injury Study in a Rat Model.
abstract: BACKGROUND
  Reperfusion injury (RI) has an important impact on the clinical prognosis for patients with acute myocardial injury who had their coronary blood flow reestablished. However, no studies to date have investigated the timeframe of coronary occlusion and reperfusion effects on RI.
  
  
  METHODS
  A total of 100 rats were divided into 4 groups based on the coronary ligation period: 30, 60, 120, and 180 min, and each group was further divided into 5 subgroups with different reperfusion periods: 0, 30, 60, 120, and 180 min. R0 was the baseline of each subgroup. All animals received the same protocols for designed ligation and reperfusion periods. Evans blue and 2,3,5-triphenyltetrazolium chloride were used to distinguish different myocardial injury areas: area at risk (AAR) and myocardial necrosis. The differences of the ratios of the necrotic area to AAR between each subgroup and baseline were further averaged to calculate an overall value of each heart.
  
  
  RESULTS
  The relative RI percentages showed significant differences (0.8 ± 2.3%, 4.9 ± 3.3%, 10.8 ± 3.1%, and 20.3 ± 3.6% respectively, p < 0.001) at different time points of reperfusion but not at different time points of ligation (p = 0.593). The effects of different time courses in RI showed that the L120R180 group (43.4 ± 2.3%) had the highest RI difference with the baseline group.
  
  
  CONCLUSIONS
  Maximal RI occurred at the timeframe of L120R180 in our animal model. This result may be utilized to assess the substantial benefits of RI therapies in an experimental rat model setting.
authors.affiliation: Division of Cardiology, Chiayi Chang Gung Memorial Hospital; Chiayi School, Chang Gung Institute of Technology, Chaiyi Hsien; School of Traditional Chinese Medicine, College of Medicine, Chang Gung University, Taoyuan;
authors.forename: Shih-Tai
authors.initials: ST
authors.lastname: Chang
authors.affiliation: Section of Health Informatics, Institute of Public Health, National Defense Medical Center and University, Taipei;
authors.forename: Chi-Ming
authors.initials: CM
authors.lastname: Chu
authors.affiliation: Division of Cardiology, Chiayi Chang Gung Memorial Hospital; Chiayi School, Chang Gung Institute of Technology, Chaiyi Hsien; School of Traditional Chinese Medicine, College of Medicine, Chang Gung University, Taoyuan;
authors.forename: Teng-Yao
authors.initials: TY
authors.lastname: Yang
authors.affiliation: Department of Life Science, College of Medicine, Chang Gung University, Taoyuan;
authors.forename: Li-Man
authors.initials: LM
authors.lastname: Hung
authors.affiliation: Division of Cardiology, Chiayi Chang Gung Memorial Hospital; Chiayi School, Chang Gung Institute of Technology, Chaiyi Hsien; School of Traditional Chinese Medicine, College of Medicine, Chang Gung University, Taoyuan;
authors.forename: Kuo-Li
authors.initials: KL
authors.lastname: Pan
authors.affiliation: Division of Cardiology, Chang Gung Memorial Hospital, Keelung, Taiwan.
authors.forename: Wen-Jin
authors.initials: WJ
authors.lastname: Cherng
keywords: Acute myocardial infarction (AMI); Coronary artery disease (CAD); Primary coronary intervention; Reperfusion injury (RI)