Utilization of Ascorbic Acid During Platelet Aggregation 1

Abstract

Conclusion

In 15 human subjects the concentration of ascorbic acid in platelets was 62.8 ± 5.6 (SEM) μg/10¹⁰ platelets and the level in cell-free plasma was 115.2 ± 10.8 (SEM) μg/100 ml. A direct correlation was found between the degree of platelet aggregation induced by thrombin, epinephrine, collagen, and ADP and the net loss of ascorbic acid from the platelets. In subjects who had ingested aspirin, platelet aggregation by epinephrine was minimal or absent and there was either no loss or a net gain in ascorbic acid. In platelets from plasma anticoagulated with EDTA and incubated with thrombin, aggregation of platelets did not occur and the concentration of ascorbic acid did not change even though ADP and ATP were released. Ascorbic acid is not released into the plasma during platelet aggregation induced by various agents and is not merely present for tissue transport. It appears to serve some definite metabolic function in platelet aggregation.