Dietary fish lipids do not diminish platelet adhesion to subendothelium

Clinical trials suggest that dietary fish lipids offer protection against pathologic thrombosis. Measurements of platelet aggregation and bleeding time indicate that these protective effects are mediated in part through alterations of platelet function. We studied the effects of supplementary fish lipids (MaxEPA) on platelet adhesion to arterial subendothelium utilizing a modified Baumgartner flow chamber. Template bleeding times were also performed, and platelet lipid composition was determined by gas chromatographic analysis. The results showed that platelet lipid composition was altered significantly during the study. However, total platelet adhesion to arterial subendothelium was not changed by ingestion of fish lipids during the study period. Bleeding times showed some prolongation in most subjects (range: -1.0 to +6.75 min), with a mean change of +0.75 min. We conclude that, in individuals maintained on ad libitum diets, the supplemental amount of fish oil used in this study was enough to induce a significant alteration in platelet lipid composition, but these changes were unaccompanied by any impairment in the ability of platelets to adhere to subendothelium in our model system.