Inhibition of human platelet function by sulfatides

Sulfatides are glycolipid constituents of human platelet cell membranes and have been shown to interact with platelet-binding proteins involved in hem ostasis. Because little is known about the physiological role of sulfatides in platelet function, the effect of sulfatide on platelet adhesion, aggreg ation, release, and ristocetin-induced platelet agglutination (RIPA) was st udied. These processes are inhibited when exogenous sulfatide is present in vitro. Inhibition of aggregation induced by collagen, thrombin, and ristoc etin by sulfatide was dose dependent. Adenosine diphosphate-mediated adhesi on and aggregation were not significantly affected by sulfatide, nor was se rotonin- and epinephrine-mediated aggregation. Collagen mediate release of serotonin was reduced sulfatide. RIPA demonstrated dose-dependent inhibitio n in response to sulfatide. These results suggest that sulfatide may play a role in modulating platelet activation. Blood Coagul Fibrinolysis 11:543-5 50 (C) 2000 Lippincott Williams & Wilkins.