title: Formation of occlusive platelet aggregates in whole blood caused by low concentrations of ADP.
abstract: Minute concentrations of ADP are released when platelets are exposed to shear stress during extracorporeal flow. However, based on current methods, these low concentrations have not been shown to have a significant impact on platelet function. We report here the formation of rigid microaggregates (MA) in response to low concentrations of ADP. A newly developed light scattering whole blood aggregometer (LSWBA) was used to detect an aggregation dose response to ADP (0-2 microM) in heparinized (1.5 U/ml) human blood. Although the LSWBA showed that ADP induced MA were reversible, evidence provided by constant pressure filtration (50 mm Hg) suggested that aggregates existed as rigid particles in the blood for up to 6 minutes. The possible implications of these findings to extracorporeal circulation are discussed.
authors: Department of Chemical Engineering, Brigham Young University, Provo, Utah 84602, USA.
authors: M W
authors: MW
authors: Hall
authors: P D
authors: PD
authors: Goodman
authors: K A
authors: KA
authors: Solen
authors: S F
authors: SF
authors: Mohammad
mesh_terms: D000244:Adenosine Diphosphate / Q000008:administration & dosage / Q000009:adverse effects*; D004305:Dose-Response Relationship, Drug; D005112:Extracorporeal Circulation / Q000009:adverse effects; D006801:Humans; D066298:In Vitro Techniques; D008027:Light; D010974:Platelet Aggregation / Q000187:drug effects*; D012542:Scattering, Radiation
chemical_list: D000244:Adenosine Diphosphate