Effects of highly purified eicosapentaenoic acid on plasma beta thromboglobulin level and vascular reactivity to angiotensin II.

Eicosapentaenoic acid (EPA), the precursor fatty acid of three series of prostaglandins, has been reported to have an antiatherothrombotic potential. We gave highly purified EPA in a soft capsule (90% ethylester form of EPA; EPA-E) to 6 healthy male volunteers for 4 weeks. After the administration of 900 mg/day of EPA-E for two weeks or longer, a significant reduction in plasma beta thromboglobulin level was observed, and after 4 weeks' administration, significantly blunted pressor responsiveness to infused angiotensin II was observed. These changes were not observed 4 weeks after EPA-E had been discontinued. After 4 weeks' ingestion of EPA-E, the platelet count, mean platelet volume, platelet aggregation with adenosine diphosphate or collagen, plasma recalcification time, prothrombin time, plasma antithrombin III, fibrinogen or plasmin concentrations, serum concentrations of total cholesterol, triglycerides, total phospholipid, nonesterified fatty acid or high-density lipoprotein cholesterol were unchanged. From the data presented it can be said that EPA-E causes a mild depression of vascular contractility and of platelet aggregability in vivo and exerts a beneficial influence on several cardiovascular factors.