title: A study of hemostasis in ischemic cerebrovascular disease. II. Abnormalities in platelet ADP release, platelet cyclooxygenase regeneration time and platelet factor 3 availability.
abstract: Most earlier studies of platelet function in stroke patients have been performed in the acute phase and are hampered by diagnostic insecurity. A sample of totally 67 young adults below the age of 55, with ischemic cerebrovascular disease (TIA and minor stroke) were investigated at a late stage after acute disease and compared to 20 healthy controls. Patients with atherosclerotic signs at cerebral angiography had significantly (p less than 0.05) higher platelet factor 3 availability than angionegative patients. Unexpectedly, female patients compared to male patients had significantly (p less than 0.05) larger ADP-release after stimulation with collagen in vitro. Furthermore, when female patients were compared to female controls a significantly (p less than 0.05) increased platelet factor 3 availability was found. The results indicate that platelets in female patients may have an increased tendency to aggregate in vivo. Patients had significantly (p less than 0.01) shortened platelet cyclooxygenase regeneration half times (PRT). This was correlated to high levels of factor VIII related antigen (r=0.59) and high levels of factor VIII biological activity (r=0.67), indicating that platelets may be consumed by platelet adhesion and mural thrombi formation in abnormal vessel walls. PRT appears to be a reliable method to assess platelet function in vivo and to optimize aspirin dose and dose intervals in the individual.
mesh_terms: D000244:Adenosine Diphosphate / Q000097:blood; D000293:Adolescent; D000328:Adult; D001792:Blood Platelets / Q000378:metabolism*; D002561:Cerebrovascular Disorders / Q000097:blood*; D005260:Female; D006487:Hemostasis; D006801:Humans; D008297:Male; D008875:Middle Aged; D010088:Oxidoreductases / Q000097:blood; D010974:Platelet Aggregation; D010977:Platelet Factor 3 / Q000378:metabolism; D011451:Prostaglandin-Endoperoxide Synthases / Q000097:blood; D012306:Risk; D013997:Time Factors
chemical_list: D010977:Platelet Factor 3; D000244:Adenosine Diphosphate; D010088:Oxidoreductases; D011451:Prostaglandin-Endoperoxide Synthases