Low Frequency Electromagnetic Field Conditioning Protects against IR Injury and Contractile Dysfunction in the Isolated Rat Heart

الملخص EN

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.