title: Aspirin inhibits surface glycoprotein IIb/IIIa, P-selectin, CD63, and CD107a receptor expression on human platelets.
abstract: Platelet inhibition after aspirin therapy reduces the risk for the development of acute coronary syndromes. However, the mechanism by which aspirin affect platelets other than by prostaglandin blockade is unclear. We sought to determine the in vitro effects of aspirin on the surface expression of nine platelet receptors using whole blood flow cytometry. Blood from 24 healthy volunteers was incubated for 30 min with 1.8 and 7.2 mg/l phosphate-buffered saline-diluted acetylsalicylic acid in the presence or absence of apyrase. Platelet serotonin release, and the surface expression of platelet receptors with or without apyrase were determined using the following monoclonal antibodies: anit-CD41 [glycoprotein (GP)IIb/IIIa], CD42b (GPIb), CD62p (P-selectin), CD51/CD61 (vitronectin receptor), CD31 [platelet/endothelial cellular adhesion molecule-1 (PECAM-1)], CD107a [lysosomal associated membrane protein (LAMP)-1], CD107b (LAMP-2), CD63 (LIMP or LAMP-3), and CD151 (PETA-3). Samples were then immediately fixed with 2% paraformaldehyde, and run on the flow cytometer within 48 h. Aspirin does not affect serotonin release from human platelets. Dose-dependent inhibition of GPIIb/IIIa, P-selectin, CD63, and CD107a receptor expression was observed in the aspirin-treated whole-blood samples. Apyrase potentiates the effects of aspirin, and independently inhibits PECAM-1. In addition to the known effect of irreversibly inhibiting platelet cyclooxygenase-1, thereby blocking thromboxane A(2) synthesis, it appears that aspirin exhibits direct effects on selective major platelet receptors.
authors.affiliation: Center for Thrombosis Reseasrch, Sinai Hospital of Baltimore, Johns Hopkins University, 2401 West Belvedere Avenue, Baltimore, MD 21215, USA.
authors.forename: Marcus E
authors.initials: ME
authors.lastname: McKenzie
authors.forename: Alex I
authors.initials: AI
authors.lastname: Malinin
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Bell
authors.forename: Alex
authors.initials: A
authors.lastname: Dzhanashvili
authors.forename: Eric D
authors.initials: ED
authors.lastname: Horowitz
authors.forename: Benjamin R
authors.initials: BR
authors.lastname: Oshrine
authors.forename: Dan
authors.initials: D
authors.lastname: Atar
authors.forename: Victor L
authors.initials: VL
authors.lastname: Serebruany
mesh_terms: D000328:Adult; D015703:Antigens, CD / Q000187:drug effects; D001241:Aspirin / Q000494:pharmacology*; D001792:Blood Platelets / Q000187:drug effects* / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D052118:Lysosomal-Associated Membrane Protein 1; D052119:Lysosomal-Associated Membrane Protein 2; D051907:Lysosomal Membrane Proteins; D008297:Male; D019007:P-Selectin / Q000187:drug effects; D015539:Platelet Activation / Q000187:drug effects; D019039:Platelet Glycoprotein GPIIb-IIIa Complex / Q000187:drug effects; D010980:Platelet Membrane Glycoproteins / Q000037:antagonists & inhibitors / Q000187:drug effects*; D012701:Serotonin / Q000378:metabolism; D060149:Tetraspanin 30
chemical_list: D015703:Antigens, CD; C554586:CD63 protein, human; D052118:Lysosomal-Associated Membrane Protein 1; D052119:Lysosomal-Associated Membrane Protein 2; D051907:Lysosomal Membrane Proteins; D019007:P-Selectin; D019039:Platelet Glycoprotein GPIIb-IIIa Complex; D010980:Platelet Membrane Glycoproteins; D060149:Tetraspanin 30; D012701:Serotonin; D001241:Aspirin