title: Low-dose aspirin does not lower in vivo platelet activation in healthy smokers.
abstract: Smoking causes atherosclerosis, and smokers have increased thromboxane (TXA2) formation. As aspirin inhibits TXA2 production we speculated that smokers would preferentially profit from inhibition of the TXA2 pathway by aspirin. Increased expression of P-selectin, a constituent of the alpha-granules of platelets, and increased levels of circulating (c)P-selectin in plasma are markers for platelet activation. The aim of this study was to compare P-selectin expression on platelets between smokers and nonsmokers, and to compare with placebo the effect of 2 weeks administration of 100 mg/d aspirin on platelet activation in smokers. Smokers exhibited higher P-selectin expression on platelets than non-smokers (2.7+/-1.8% v 1.6+/-0.6%, P=0.018), thus confirming increased platelet activation. Aspirin did not reduce platelet activation as demonstrated by unchanged P-selectin expression on platelets and cP-selectin plasma levels.
authors.affiliation: Department of Clinical Pharmacology, Clinical Institute of Medical and Chemical Laboratory Diagnostics, Vienna, Austria.
authors.forename: T
authors.initials: T
authors.lastname: Pernerstorfer
authors.forename: P
authors.initials: P
authors.lastname: Stohlawetz
authors.forename: G
authors.initials: G
authors.lastname: Stummvoll
authors.forename: S
authors.initials: S
authors.lastname: Kapiotis
authors.forename: T
authors.initials: T
authors.lastname: Szekeres
authors.forename: H G
authors.initials: HG
authors.lastname: Eichler
authors.forename: B
authors.initials: B
authors.lastname: Jilma
mesh_terms: D000328:Adult; D001241:Aspirin / Q000008:administration & dosage / Q000494:pharmacology*; D001792:Blood Platelets / Q000378:metabolism; D018592:Cross-Over Studies; D004311:Double-Blind Method; D006801:Humans; D019007:P-Selectin / Q000378:metabolism; D015539:Platelet Activation / Q000187:drug effects*; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage*; D011446:Prospective Studies; D012907:Smoking / Q000097:blood*; D013931:Thromboxanes / Q000378:metabolism
chemical_list: D019007:P-Selectin; D010975:Platelet Aggregation Inhibitors; D013931:Thromboxanes; D001241:Aspirin