Age-related increased 14C-arachidonic acid uptake by platelets in normal subjects.

Arachidonic acid uptake activity (pmol/10(8) platelets min) measured in platelets obtained from normal subjects was significantly higher in over-forty year old (3.53 +/- 0.38) than in under-forty year old subjects (2.33 +/- 0.12). No significant correlations were found between the arachidonic acid uptake activity and fasting plasma glucose, total cholesterol, HDL-cholesterol or triglyceride levels. The arachidonic acid uptake activity was significantly reduced by the presence of indomethacin in platelets obtained from both under and over-forty year old subjects, and by the presence of nordihydroguaiaretic acid in platelets obtained from over-forty year old subjects. In conclusion, these data show that arachidonate uptake activity by platelets increased with age. This increase was abolished when platelets were incubated in the presence of inhibitors of the arachidonic acid metabolism.