title: Comparative study of the cardioprotective effects of local and remote preconditioning in ischemia/reperfusion injury.
abstract: OBJECTIVE
  Though the cardioprotective effects of local or remote preconditioning have been estimated, it is still unclear which of them is more reliable and provides more cardioprotection. The present investigation was directed to compare, in one study, the cardioprotective effects of different cycles of local or remote preconditioning in ischemia/reperfusion (I/R)-induced electrophysiological, biochemical and histological changes in rats.
  
  
  METHODS
  Rats were randomly assigned into 10 groups. Groups 1 and 2 were normal and I/R groups, respectively. Other groups were subjected to 1, 2, 3, 4 cycles of local or remote preconditioning before myocardial I/R (40 min/10 min). Heart rate and ventricular arrhythmias were recorded during I/R progress. At the end of reperfusion, plasma creatine kinase-MB (CK-MB) activity and total nitrate/nitrite (NO(x)) were determined. In addition, lactate, adenine nucleotides, thiobarbituric acid reactive substances (TBARS), reduced glutathione (GSH) and myeloperoxidase (MPO) activity were estimated in the heart left ventricle. Histological examination was also performed to visualize the protective cellular effects of the effective cycle of local or remote preconditioning.
  
  
  RESULTS
  In general, local preconditioning was more effective than remote preconditioning in reducing ventricular arrhythmias, CK-MB release, lactate accumulation and elevated MPO activity as well as preserving adenine nucleotides. Concerning the most effective group in each therapy, 3 cycles of local preconditioning provided more cardioprotection than that of remote preconditioning in the histological examination.
  
  
  CONCLUSIONS
  Despite being invasive, local preconditioning provided more effective cardioprotection than remote preconditioning in ameliorating the overall electrophysiological, biochemical and histological changes.
authors.affiliation: Department of Pharmacology and Toxicology, Faculty of Pharmacy, Cairo University, Kasr El Aini Street, Cairo, Egypt. lamiaahmed2004@yahoo.com
authors.forename: Lamiaa A
authors.initials: LA
authors.lastname: Ahmed
authors.forename: Hesham A
authors.initials: HA
authors.lastname: Salem
authors.forename: Amina S
authors.initials: AS
authors.lastname: Attia
authors.forename: Azza M
authors.initials: AM
authors.lastname: Agha
mesh_terms: D000818:Animals; D001145:Arrhythmias, Cardiac; D052279:Creatine Kinase, MB Form / Q000097:blood / Q000378:metabolism; D006339:Heart Rate; D019157:Ischemic Preconditioning, Myocardial; D008297:Male; D015428:Myocardial Reperfusion Injury / Q000517:prevention & control*; D009566:Nitrates / Q000097:blood; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D015427:Reperfusion Injury / Q000517:prevention & control*
chemical_list: D009566:Nitrates; D052279:Creatine Kinase, MB Form