title: Glycoprotein Ia/IIa-mediated activation-dependent platelet adhesion to collagen.
abstract: In the presence of anti-glycoprotein (GP) IIb/IIIa antibody at the concentration which completely inhibit platelet aggregation, ADP (0.5-3 microM) increased platelet adhesion to collagen in a concentration-dependent manner under static conditions when platelet-rich plasma (PRP) was used for the assay instead of washed platelets. This was also supported by the results of scanning electron microscopic analyses. The ADP-induced platelet adhesion to collagen was inhibited by PGI2 or beraprost, a stable analogue of PGI2, in a concentration-dependent manner (1-10 ng/ml). These findings suggested the presence of activation-dependent platelet adhesion to collagen. ADP-induced platelet adhesion to collagen was almost completely inhibited by anti-GPIa/IIa and anti-GPIIa antibodies. In the present study, we provide the first direct evidence that the activation-dependent platelet adhesion to collagen is induced by ADP and that GPIa/IIa also plays an important role in the mechanisms of this adhesion.
authors.affiliation: Laboratory of Pharmacology, Toray Industries, Inc., Kanagawa, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Kainoh
authors.forename: Y
authors.initials: Y
authors.lastname: Ikeda
authors.forename: S
authors.initials: S
authors.lastname: Nishio
authors.forename: T
authors.initials: T
authors.lastname: Nakadate
mesh_terms: D000244:Adenosine Diphosphate; D000328:Adult; D003094:Collagen / Q000097:blood*; D011464:Epoprostenol / Q000031:analogs & derivatives / Q000494:pharmacology; D005434:Flow Cytometry; D006801:Humans; D008297:Male; D008855:Microscopy, Electron, Scanning; D015539:Platelet Activation / Q000502:physiology*; D010973:Platelet Adhesiveness / Q000187:drug effects*; D010980:Platelet Membrane Glycoproteins / Q000276:immunology / Q000502:physiology*; D013915:Thrombasthenia / Q000097:blood
chemical_list: D010980:Platelet Membrane Glycoproteins; C048081:beraprost; D000244:Adenosine Diphosphate; D003094:Collagen; D011464:Epoprostenol