How Does Ristocetin Cause Platelet Aggregation?

How Does Ristocetin Cause Platelet Aggregation? In an unknown fashion, the antibiotic ristocetin causes von Willebrand factor to bind the platelet receptor glycoprotein Ib (GpIb), so when ristocetin is added to normal blood, it causes agglutination of fixed platelets or initiates the initial agglutination phase of aggregation of live platelets. What causes platelet aggregation? This