Model experiments on platelet adhesion in stagnation point flow

Issue title: Special Issue for the Fifth International Congress of Biorheology. Part II. Baden-Baden, F.R. Germany, 20–24 August 1983

Guest editors: Alfred L. Copley and Siegfried Witte

Article type: Research Article

Authors: Wurzinger, L.J.^a | Blasberg, P.^b | van de Loecht, M.^b | Suwelack, W.^b | Schmid-Schönbein, H.^b

Affiliations: [a] Abteilungen Anatomie der RWTH Aachen, Schneebergweg 211,5100 Aachen, W. Germany | [b] Physiologie der RWTH Aachen, Schneebergweg 211,5100 Aachen, W. Germany

Abstract: Experiments with glass models of arterial branchings and bends, perfused with bovine platelet rich plasma (PRP), revealed platelet deposition being strongly dependent on fluid dynamic factors. Predilection sites of platelet deposits are characterized by flow vectors directed against the wall, so-called stagnation point flow. Thus collision of suspended particles with the wall, an absolute prerequisite for adhesion of platelets to surfaces even as thrombogenic as glass, appears mediated by convective forces. The extent of platelet deposition is correlated to the magnitude of flow components normal to the surface as well as to the state of biological activation of the platelets. The latter could be effective by an increase in hydrodynamically effective volume, invariably associated with the platelet shape change reaction to biochemical stimulants like ADP. The effect of altered rheological properties of platelets upon their deposition and of mechanical properties of surfaces was examined in a stagnation point flow chamber. Roughnesses in the order of 5 µm, probably by creating local flow disturbances, significantly enhance platelet adhesion, as compared to a smooth surface of identical chemical composition.

Keywords: platelet adhesion, stagnation point, atherogenesis, platelet rheology, shape change

DOI: 10.3233/BIR-1984-21422

Journal: Biorheology, vol. 21, no. 4, pp. 649-659, 1984