title: The effect of serum amyloid protein A fragment-SAA25-76 on blood platelet aggregation.
abstract: The effect of the major acute phase protein serum amyloid A (SAA) on collagen induced platelet aggregation was investigated. A truncated version of SAA, SAA25-76 was tested for inhibitory capacity of collagen induced platelet aggregation in platelet-rich plasma (PRP) and whole blood (WB). The tetrapeptide RGDV, a known inhibitor of platelet aggregation, was included as a reference compound. SAA25-76 at a concentration of 390 micrograms/ml inhibited platelet aggregation induced by 1 microgram/ml of collagen in PRP. This corresponds to the plasma concentration of SAA during an acute phase response. However, the inhibitory effect of the SAA25-76 fragment was lost at higher collagen concentrations (> or = 2.0 micrograms/ml). The SAA fragment at 390 micrograms/ml had no significant effect on platelet aggregation in WB. In contrast, RGDV blocked collagen induced platelet aggregation in both PRP and WB.
authors.affiliation: Department of Biochemistry/Biotechnology Centre of Oslo, University of Oslo, Norway.
authors.forename: P V
authors.initials: PV
authors.lastname: Syversen
authors.forename: U
authors.initials: U
authors.lastname: Saeter
authors.forename: L
authors.initials: L
authors.lastname: Cunha-Ribeiro
authors.forename: U
authors.initials: U
authors.lastname: Orvim
authors.forename: K
authors.initials: K
authors.lastname: Sletten
authors.forename: G
authors.initials: G
authors.lastname: Husby
authors.forename: K S
authors.initials: KS
authors.lastname: Sakariassen
mesh_terms: D000595:Amino Acid Sequence; D003094:Collagen / Q000037:antagonists & inhibitors; D006801:Humans; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000494:pharmacology; D010446:Peptide Fragments / Q000494:pharmacology*; D010974:Platelet Aggregation / Q000187:drug effects*; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology; D010976:Platelet Count; D000685:Serum Amyloid A Protein / Q000494:pharmacology*
chemical_list: D009842:Oligopeptides; D010446:Peptide Fragments; D010975:Platelet Aggregation Inhibitors; D000685:Serum Amyloid A Protein; D003094:Collagen; C086684:arginyl-glycyl-aspartyl-valine