The effect of fish oil consumption on platelet aggregation responses in washed human platelet suspensions

Although the biochemical mechanisms relating to the inhibitory action of eicosapentaenoic acid on platelet function have previously been investigated in washed platelet suspensions, there is little existing evidence in washed platelet suspensions to indicate that dietary fish oil consumption reduces platelet aggregation responses. In the present work, eight healthy male volunteers consumed 20 fish oil capsules (MaxEPA) per day for a period of six weeks followed by a six week "dry-out" period during which no fish oil was consumed. Washed platelet suspensions were prepared and aggregation responses to collagen, platelet activating factor (PAF), and thrombin were assessed initially at week 0 and subsequently at 3, 6, 9, and 12 weeks of the experimental period. Three weeks of fish oil consumption did not produce any marked alterations in aggregation responses; however, six weeks of dietary fish oil supplementation resulted in decreased maximum aggregation responses to collagen and PAF by 50.1% and 27.2%, respectively. These results provide evidence, in washed platelet suspensions, that dietary fish oil consumption significantly diminishes platelet responses to collagen and PAF. The significance of these observations remains to be explored and interpreted.