Abstract
There is little known on the antithrombotic effects of niceritrol, such as on platelet retension and aggregation. Methods: (1) After over night fasting, blood samples were obtained from healthy volunteers before and 4 hr after single dose of oral administration of 500mg niceritrol. Platelet retension on glass beads column and aggregation were measured. Conversion of 14C-arachidonic acid (AA) was carried out for 1 min in washed platelet. (2) Two groups of Rabbits were fed either control diet or high cholesterol diet. Each group was further divided into two subgroups. One subgroup was administered niceretrol 150mg/kg/day, and the other was not. After 4 and 8 weeks of feeding, rabbits were sacrificed. The production of prostacyclin-like substance by a thoracic aorta was measured by the inhibition of human platelet aggregation and by the RIA of 6-keto-PGF1α. Results: (1) A single dose of oral administration of niceritrol to the volunteers significantly decreased collagen induced platelet aggregation. The conversion rate of 14C-AA to TXB2 in platelet suspension was significantly decreased (18.9± 4.9% to 7.7±4.4%, p<0.001). Platelet retension was decreased. (2) In every subgroup, niceritrol exerted no effect on prostacycline-like substance production by aortas.
