title: Response of thromboxane B2, malondialdehyde and platelet sensitivity to 3 weeks low-dose aspirin (ASA) in healthy volunteers.
abstract: To examine the effects of low-dose aspirin thromboxane B2 (TXB2), malondialdehyde (MDA) and platelet sensitivity to prostaglandin I2 (PGI2) have been measured in a total of 18 healthy volunteers. They were randomly assigned to 3 groups, 6 volunteers each, receiving either 1, 10 or 20 mg ASA orally a day for 3 weeks in a double-blind fashion. In order to assess the time course of ASA-induced changes, blood was drawn before, 1 hour and 2, 3, 5, 7, 9, 12, 14, 16 and 21 days after the first drug-intake. Serum-TXB2 was depressed time- and dose-dependently, after 1 mg daily to about 60%, after 10 mg to about 30%, after 20 mg to about 5% of controls. MDA-formation and conversion of exogenously added arachidonic acid (AA) to TXB2 also dropped significantly, (p less than 0.01), the extent depending on the ASA-dosage administered. The drop in MDA- and TXB2-values in the 3 groups correlated with r = 0.98, 0.94, 0.98, respectively. The platelet sensitivity during 20 and 10 mg ASA-administration did not change at all, whereas a significant increase (p less than 0.01) in platelet sensitivity during treatment with 1 mg ASA was observed.
authors.affiliation: Atherosclerosis Research Group (ASF), Vienna, Austria.
authors.forename: H
authors.initials: H
authors.lastname: Sinzinger
authors.forename: I
authors.initials: I
authors.lastname: Virgolini
authors.forename: B A
authors.initials: BA
authors.lastname: Peskar
mesh_terms: D000328:Adult; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000097:blood; D001241:Aspirin / Q000008:administration & dosage / Q000494:pharmacology*; D011464:Epoprostenol / Q000494:pharmacology; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D008314:Malonates / Q000097:blood*; D008315:Malondialdehyde / Q000097:blood*; D010974:Platelet Aggregation / Q000187:drug effects*; D013929:Thromboxane B2 / Q000097:blood*
chemical_list: D001095:Arachidonic Acids; D008314:Malonates; D016718:Arachidonic Acid; D008315:Malondialdehyde; D013929:Thromboxane B2; D011464:Epoprostenol; D001241:Aspirin