[Biphasic effects of a combined administration of SOD and CAT on Ca overload and recovery of function and metabolites].
The present study was performed to clarify whether the combination of superoxide dismutase (SOD) and catalase (CAT) can reduce Ca2+ overload and improve recovery of function and metabolites during reperfusion in isolated globally ischemic rat hearts. In non-treated hearts, left ventricular developed pressure (LVDP) recovered to only 30% of the preischemic value with elevation of left ventricular end-diastolic pressure (LVEDP) after 30 min of reperfusion following 30 min of global zero-flow ischemia. ATP and CP fell by 40% and 60%, respectively with 13 fold increase in Ca2+ uptake. A combined administration of SOD and CAT at low concentrations improved recovery of function (LVDP to 60%), reduced Ca2+ uptake (10 fold) without any improvement in high energy phosphates. However a combination of SOD and CAT at higher concentrations did not improve, or even deteriorate functional and metabolic recovery with increased Ca2+ overload (12 to 14 fold). These results indicated that the extracellular free radical scavengers, SOD and CAT, had a biphasic effect on reperfusion injury and could be partially beneficial at low concentrations.
Tani
M
M
Department of Geriatrics, Keio Gijuku University School of Medicine.
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002374:Catalase / Q000494:pharmacology* / Q000627:therapeutic use; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D004734:Energy Metabolism / Q000187:drug effects*; D016166:Free Radical Scavengers; D066298:In Vitro Techniques; D008297:Male; D015425:Myocardial Reperfusion; D015428:Myocardial Reperfusion Injury / Q000188:drug therapy; D009206:Myocardium / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D013482:Superoxide Dismutase / Q000494:pharmacology* / Q000627:therapeutic use
D016166:Free Radical Scavengers; D002374:Catalase; D013482:Superoxide Dismutase; D002118:Calcium