EFFECTS OF EICOSAPENTAENOIC ACID AND DOCOSAHEXAENOIC ACID DIET SUPPLEMENT ON TOLERANCE TO THE CARDIOTOXICITY OF EPIRUBICIN AND TO ISCHEMIA-REPERFUSION IN THE ISOLATED RAT-HEART

We compared the effects of 2 weeks dietary supplement of docosahexaeno ic acid, eicosapentaenoic acid or olive oil on myocardial tolerance to the cardiotoxicity of the anthracycline epirubicin and to ischaemia r eperfusion. Isolated rat hearts from the dietary groups were perfused at a constant flow rate of 12.5 ml/min. The hearts were subjected to a 20 min. period of epirubicin infusion by a side arm of the perfusion system at a rate of 0.2 mg/min. or a 20 min. period of global ischaemi a. After 10 min. of epirubicin infusion a significantly (P<0.05) highe r aortic pressure (an index of coronary resistance during constant flo w perfusion) was observed in the olive oil group; 130+/-22% (mean+/-S. D.) compared to hearts in the docosahexaenoic acid; 108+/-9% (mean+/-S .D.), and eicosapentaenoic acid; 105+/-7% (mean+/-S.D.), group. Hearts from docosahexaenoic acid-fed rats showed a significantly increased l eft ventricular end-diastolic pressure (an index of contracture); of 6 6+/-30 mmHg (mean+/-S.D.) after 15 min. of global ischaemia compared t o eicosapetaenoic acid fed rats; 37+/-18 mmHg (mean+/-S.D.), and signi ficantly higher release of lactate dehydrogenase during the following 30 min. period of reperfusion compared to olive oil-fed rats. We concl ude that eicosapentaenoic acid and docosahexaenoic acid could be usefu l during epirubicin infusion and that docosahexaenoic acid could be ha rmful during ischaemia reperfusion.