EFFECTS OF FLOW PULSATILITY ON PLATELET ADHESION TO SUBENDOTHELIUM

Platelet adhesion studies in perfusion chambers are generally performed with constant flow rate or with pulsatile flow generated by a roller pump. No information is available about the effect of flow pulsatility in the physiological range. For this purpose we devised a system consisting of a eccentric rotating disc which forces a driver toward a flexible tube. This movement causes a sinusoidal laminar flow component. The effect of this sinusoidal pulse on platelet adhesion was studied with the annulai^perfusion chamber of Baumgartner using umbilical arteries and In-labeled platelets. Conditions used are described below, where γ [1/s] is the constant flow component, γ₀ [1/s] is the amplitude of the sinusoidal component and f [beats/min] is the frequency of the pulse (70 beats/min standard). Adhesion values are expressed as 10^{5 III} In platelets/cm² (n=4).

When osciallatory flow (abence of constant component) was generated, platelet adhesion incersed with increasing amplitude of the pulse.

These data indicate that pulsatility as persent in the the aorta and large arteries has no effect on platelet adhesion.