Jr. Obrien et Md. Etherington, HIGH SHEAR-INDUCED PLATELET ACTIVATION AND INACTIVATION - THE IMPORTANCE OF METHODOLOGY, Blood coagulation & fibrinolysis, 7(2), 1996, pp. 228-232
High shear platelet activation may be conveniently studied by forcing
blood through a tine tilter in the filterometer. To achieve haemostasi
s in vivo platelets are activated When haemostasis is achieved, inacti
vation must follow. In the filterometer, activation occurs with filter
blocking (first phase) and after 100 s inactivation ('rebleeding') ma
y occur (second phase). We report the effect of different pressures, t
emperatures, incubation times, anticoagulants and aspirin in this syst
em Most 'rebleeding' occurred in citrate, followed by native blood, r-
hirudin and low-molecular-weight heparin. Unfractionated heparin inhib
ited 'rebleeding' whereas aspirin potentiated it. These and other find
ings are technically and clinically relevant and contribute to an unde
rstanding of the mechanisms involved in 'rebleeding' and hence perhaps
in thrombogenesis.