PH-DEPENDENCE OF QUANTITATIVE RISTOCETIN-INDUCED PLATELET-AGGREGATION - THEORETICAL AND PRACTICAL IMPLICATIONS - NEW DEVICE FOR MAINTENANCE OF PLATELET-RICH PLASMA PH

Google Scholar
  • 1 January 1976
    • journal article
    • research article
    • Vol. 47  (5) , 841-854
Abstract
Quantitative ristocetin-induced platelet aggregation of normal human platelet-rich plasma (PRP) decreased with time after PRP preparation. An increase in pH of the PRP with time was responsible for this finding. Diffusion of CO2 from the plasma was the prime determinant of the change in pH. Since a complex combination of factors influences CO2 diffusion (surface area-to-volume relationship, capping, mixing, etc.) the change in pH was variable with time. Quantitative ristocetin aggregation should be pH controlled. A simple device for maintaining PRP pH constant by control of the ambient CO2 tension was designed and found effective in keeping both pH and quantitative ristocetin aggregation constant over a prolonged period of time. It can be adapted for use in platelet aggregation studies employing other reagents. The pH dependence of ristocetin-induced platelet aggregation was consistent with other data supporting an electrostatic interaction between the platelet, von Willebrand factor and ristocetin. A model wherein ristocetin neutralizes some of the platelet''s negative charge and permits the von Willebrand factor to bridge sites on separate platelets to induce agglutination is discussed.

This publication has 1 reference indexed in Scilit: