title: Effects of hydrogen peroxide on cardiac function and post-ischaemic functional recovery in the isolated 'working' rat heart.
abstract: The effects of hydrogen peroxide on the normal and ischaemic myocardium were investigated using the isolated 'working' rat heart preparation. In the range 0-3 microM no changes in heart rate, aortic flow, coronary flow, or aortic pressure were observed. Between 3 and 30 microM, however, there was a dose-dependent fall in aortic flow and an accompanying increase in coronary flow, the total cardiac output remaining unchanged. At concentrations about 30 microM functional failure occurred. Following a 24-min ischaemic period during which time 6 microM hydrogen peroxide was infused via the aorta at a constant rate to remove any vasodilatory effect, all hearts failed to recover. In contrast, 50% of control hearts recovered pump function. In conclusion, therefore, hydrogen peroxide can reduce function in the aerobic working rat heart and may exert a vasodilatory effect. When this effect is eliminated hydrogen peroxide affords no protection during ischaemia and appears to exacerbate tissue injury.
mesh_terms: D000818:Animals; D003326:Coronary Circulation / Q000187:drug effects; D003327:Coronary Disease / Q000503:physiopathology*; D006321:Heart / Q000187:drug effects*; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D066298:In Vitro Techniques; D008297:Male; D051381:Rats
chemical_list: D006861:Hydrogen Peroxide