Clq inhibition of the interaction of collagen with human platelets.
Human Clq, isolated in pure state after affinity chromatography on IgG-Sepharose, inhibited collagen-induced aggregation and release of 14C-Serotonin from prelabeled human platelets. Platelet aggregation induced by ADP or thrombin was not inhibited by Clq. Also, the adherence of platelets to glass surfaces was significantly diminished by Clq. In contrast, aggregated Clq mimicked the effect of collagen in causing platelet aggregation and release of serotonin. It appears that monomeric Clq, which has structural similarities to collagen competes with collagen for specific sites on the platelet surface.
D000244:Adenosine Diphosphate / Q000494:pharmacology; D001792:Blood Platelets / Q000502:physiology*; D003094:Collagen / Q000494:pharmacology / Q000502:physiology*; D003172:Complement C1 / Q000502:physiology*; D003165:Complement System Proteins / Q000502:physiology*; D006801:Humans; D010974:Platelet Aggregation / Q000187:drug effects; D012701:Serotonin / Q000502:physiology; D013917:Thrombin / Q000494:pharmacology
D003172:Complement C1; D012701:Serotonin; D000244:Adenosine Diphosphate; D003094:Collagen; D003165:Complement System Proteins; D013917:Thrombin