Hydrogen peroxide enhances iron-induced injury in isolated heart and ventricular cardiomyocyte in rats.
To explore the cardiac effects of iron with or without hydrogen peroxide, the isolated perfused rat heart and enzymatically isolated ventricular cardiomyocyte were used. It was shown that treatment with cell-permeable iron (Fe-HQ) for 10 min reduced the contractile amplitude and velocity and end diastolic cell length in the cardiomyocyte and increased the contents of lactate dehydrogenase (LDH) and creatine kinase (CK) in the coronary effluent and malondialdehyde (MDA) in the myocardium. The left ventricular developed pressure (LVDP), +/-dP/dtmax, and heart rate and coronary flow are showed a biphasic phase, an increase at first followed by a decline. Treatment with hydrogen peroxide for 10 min following Fe-HQ augmented the effect of iron with an increase in coronary LDH and CK release and myocardial MDA content, and decrease in LVDP, +/-dP/dtmax and heart rate. Perfusion of reduced glutathione with hydrogen peroxide counteracted these effects of Fe-HQ and hydrogen peroxide while dimethyl sulfoxide had no effect on the injury induced by Fe-HQ and hydrogen peroxide in the isolated rat heart. This suggests that augmentation of myocardial injury as a result of an increase in intracellular iron by hydrogen peroxide might involve the dysfunction of sulfydryl group containing proteins but not the hydroxyl radicals.
Chen
Ying Ying
YY
Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, PRC.
Ho
Kwok Pin
KP
Xia
Qiang
Q
Qian
Zhong Ming
ZM
D000818:Animals; D001783:Blood Flow Velocity / Q000187:drug effects; D002478:Cells, Cultured; D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D006335:Heart Injuries / Q000139:chemically induced* / Q000503:physiopathology; D006352:Heart Ventricles / Q000187:drug effects* / Q000503:physiopathology; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D007501:Iron / Q000633:toxicity*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors; D018487:Ventricular Dysfunction, Left / Q000139:chemically induced
D006861:Hydrogen Peroxide; D007501:Iron; D004121:Dimethyl Sulfoxide