Dauricine inhibits redistribution of platelet membrane glycoprotein IV andrelease of intracellular alpha-granule thrombospondin induced by thrombin

AIM: To study the possibility of dauricine (Dau) inhibiting redistribution of platelet membrane glycoprotein IV (GPIV) and release of intracellular al pha-granule thrombospondin (TSP) on platelet activation. METHODS: Using the flow cytometric assay of washed platelet to record expression of GPIV and release of TSP induced by thrombin. RESULTS: Dau did not affect GPIV and TS P on resting platelet membrane but inhibited redistribution of GPIV to the platelet surface and TSP release on activated platelet. There was a marked positive correlation between changes of GPIV and TSP (r = 0.511, P < 0.01). The inhibitory effect of Dau appeared not to be Ca2+ concentration-depende nt. CONCLUSION: Dau inhibited redistribution of GPIV and release of intrace llular a-granule thrombospondin induced by release induced intracellular th rombin.