title: Low Frequency Electromagnetic Field Conditioning Protects against I/R Injury and Contractile Dysfunction in the Isolated Rat Heart.
abstract: Low frequency electromagnetic field (LF-EMF) decreases the formation of reactive oxygen species, which are key mediators of ischemia/reperfusion (I/R) injury. Therefore, we hypothesized that the LF-EMF protects contractility of hearts subjected to I/R injury. Isolated rat hearts were subjected to 20 min of global no-flow ischemia, followed by 30 min reperfusion, in the presence or absence of LF-EMF. Coronary flow, heart rate, left ventricular developed pressure (LVDP), and rate pressure product (RPP) were determined for evaluation of heart mechanical function. The activity of cardiac matrix metalloproteinase-2 (MMP-2) and the contents of coronary effluent troponin I (TnI) and interleukin-6 (IL-6) were measured as markers of heart injury. LF-EMF prevented decreased RPP in I/R hearts, while having no effect on coronary flow. In addition, hearts subjected to I/R exhibited significantly increased LVDP when subjected to LF-EMF. Although TnI and IL-6 levels were increased in I/R hearts, their levels returned to baseline aerobic levels in I/R hearts subjected to LF-EMF. The reduced activity of MMP-2 in I/R hearts was reversed in hearts subjected to LF-EMF. The data presented here indicate that acute exposure to LF-EMF protects mechanical function of I/R hearts and reduces I/R injury.
authors.affiliation: Department and Clinic of Cardiology, Medical University of Wroclaw, 50-556 Wroclaw, Poland.
authors.forename: Dariusz
authors.initials: D
authors.lastname: Bialy
authors.affiliation: Department of Medical Emergency, Medical University of Wroclaw, 51-616 Wroclaw, Poland.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Wawrzynska
authors.affiliation: Department of Clinical Chemistry, Medical University of Wroclaw, 50-556 Wroclaw, Poland.
authors.forename: Iwona
authors.initials: I
authors.lastname: Bil-Lula
authors.affiliation: Department of Clinical Chemistry, Medical University of Wroclaw, 50-556 Wroclaw, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Krzywonos-Zawadzka
authors.affiliation: Department of Clinical Chemistry, Medical University of Wroclaw, 50-556 Wroclaw, Poland ; Department of Pharmacology, College of Medicine, University of Saskatchewan, 107 Wiggins Road, Saskatoon, SK, Canada S7N 5E5.
authors.forename: Mieczyslaw
authors.initials: M
authors.lastname: Wozniak
authors.affiliation: Faculty of Pharmacy, University of Montreal, Montreal, QC, Canada H3T 1J4.
authors.forename: Virgilio J J
authors.initials: VJ
authors.lastname: Cadete
authors.affiliation: Department of Clinical Chemistry, Medical University of Wroclaw, 50-556 Wroclaw, Poland ; Department of Pharmacology, College of Medicine, University of Saskatchewan, 107 Wiggins Road, Saskatoon, SK, Canada S7N 5E5.
authors.forename: Grzegorz
authors.identifier: 0000-0003-1596-2133
authors.initials: G
authors.lastname: Sawicki
mesh_terms: D000818:Animals; D003326:Coronary Circulation / Q000528:radiation effects; D004574:Electromagnetic Fields; D006801:Humans; D015850:Interleukin-6 / Q000378:metabolism; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism; D009200:Myocardial Contraction / Q000502:physiology / Q000528:radiation effects*; D015428:Myocardial Reperfusion Injury / Q000378:metabolism / Q000503:physiopathology* / Q000628:therapy*; D009206:Myocardium / Q000473:pathology; D009924:Organ Culture Techniques; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism; D019210:Troponin I / Q000378:metabolism
chemical_list: D015850:Interleukin-6; D017382:Reactive Oxygen Species; D019210:Troponin I; D020778:Matrix Metalloproteinase 2