1. Exercise-induced cardioprotection is mediated by a bloodborne, transferable factor
- Author
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Andrew N. Redington, E. Jean St-Michel, Hans Erik Bøtker, Michael Schmidt, Michael B. Tropak, Rebekka Vibjerg Jensen, M. M. Michelsen, Bo Løfgren, and Nicolaj B. Støttrup
- Subjects
Adult ,Male ,medicine.medical_specialty ,Time Factors ,Adolescent ,Physiology ,medicine.drug_class ,Narcotic Antagonists ,Ischemia ,Myocardial Infarction ,Physical exercise ,Myocardial Reperfusion Injury ,(+)-Naloxone ,In Vitro Techniques ,Ventricular Function, Left ,Upper Extremity ,Young Adult ,Opioid receptor ,Physiology (medical) ,Internal medicine ,Paracrine Communication ,medicine ,Ventricular Pressure ,Animals ,Humans ,Blood Transfusion ,Lactic Acid ,Ischemic Preconditioning ,Exercise ,Cardioprotection ,business.industry ,Naloxone ,Myocardium ,Antagonist ,Hemodynamics ,medicine.disease ,Infarct size ,Anesthesia ,Cardiology ,Ischemic preconditioning ,Rabbits ,Cardiology and Cardiovascular Medicine ,business - Abstract
Exercise protects against myocardial ischemia-reperfusion (I-R) injury but the mechanism remains unclear. Protection can be transferred from a remotely preconditioned human donor to an isolated perfused rabbit heart using a dialysate of plasma. We hypothesized that physical exercise preconditioning also confers cardioprotection through a humorally mediated effector dependent on opioid receptor activation. Thirteen male volunteers performed vigorous exercise (four 2-minute bouts of high-intensity exercise) and 1 week later they underwent remote ischemic preconditioning (four cycles of 5 min upper limb ischemia and reperfusion). Dialysates were prepared from blood collected before (control) and after the two interventions. Isolated rabbit hearts were perfused with the dialysates without and with co-administration of naloxone (opioid receptor antagonist) prior to 40 min regional ischemia and 2 h reperfusion. Exercise and remote ischemic preconditioning (rIPC) reduced infarct size from 60 ± 5 to 35 ± 5 % and from 57 ± 7 to 27 ± 3 % of the area at risk, respectively (p
- Published
- 2011
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