THE CARDIOVASCULAR PROTECTIVE ROLE OF DOCOSAHEXAENOIC ACID

Dietary fish oils rich in n-3 polyunsaturated fatty acids can modulate a diverse range of factors contributing to cardiovascular disease. Th is study examined the relative roles of eicosapentaenoic acid (20:5 n- 3; EPA) and docosahexaenoic acid (22:6 n-3; DHA) which are the princip al n-3 polyunsaturated fatty acids regarded as candidates for cardiopr otective actions. At low dietary intakes (0.4-1.1% of energy (%en)), d ocosahexaenoic acid but not eicosapentaenoic acid inhibited ischaemia- induced cardiac arrhythmias. At intakes of 3.9-10.0%en, docosahexaenoi c acid was more effective than eicosapentaenoic acid at retarding hype rtension development in spontaneously hypertensive rats (SHR) and inhi biting thromboxane-like vasoconstrictor responses in aortas from SHR. In stroke-prone SHR with established hypertension, docosahexaenoic aci d (3.9-10.0%en) retarded the development of salt-loading induced prote inuria but eicosapentaenoic acid alone was ineffective. The results de monstrate that purified n-3 polyunsaturated fatty acids mimic the card iovascular actions of fish oils and imply that docosahexaenoic acid ma y be the principal active component conferring cardiovascular protecti on.