STUDIES IN PATIENTS WITH BLEEDING DISORDERS SHOW THAT PLATELET-VESSEL INTERACTION IS IMPORTANT FOR THROMBOXANE FORMATION IN BLEEDING-TIME WOUNDS

The production of thomboxane B2, the primary metabolite of thromboxane A2, and 6-keto prostaglandin F1∝, the primary metabolite of prostacyclin, were measured in response to a standardized vascular injury, the bleeding time, in patients with von Willebrand's disease and in patients with platelet function defects. Compared to controls, thromboxane B2 levels in bleeding time blood were significantly lower in subjects with von Willebrand's disease. In patients with platelet function defects associated with a deficient response to thromboxane A2, thromboxane B2 production in bleeding time blood was similar to controls. In subjects with other platelet function defects, thromboxane production was significantly lower than normal. 6-keto PGF1∝ production in bleeding time blood was not significantly different in patients compared to controls. The results suggest that bleeding time thromboxane production is influenced by the extent of platelet-vessel interaction. © 1990.