Objective: To investigate the effect of dauricine on the irreversible platelet aggregability of patients with
mitral stenosis
(MS). Methods: Glycoprotein Ⅳ (GPⅣ) and
thrombospondin (TSP) levels on the membrane surface of the stationary platelet or platelet activated by thrombin (0.05 U/ml, 0.1U/ml, 0.5U/ml, 1.0U/ml) in 16 patients with MS were measured with flow cytometric method and compared with those of the healthy (14 cases). Results: The GPⅣ level of stationary platelet, the GPⅣ and TSP levels of activated platelet in MS patients were higher than those in the healthy significantly (P<0 01), while the TSP level of stationary platelet was not different between the patients and the healthy (P>0 05). The GPⅣ redistribution on the activated platelet surface was apparently inhibited by dauricine (50μmol/L,P<0 05,P<0.01) and the release of TSP from intracellular α granules was inhibited by dauricine only in the activated platelets induced by thrombin of low concentration (0.05U/ml and 0.1U/ml, P<0 05,P<0.01), inhibiting effect was not found in those activated with high concentration of thrombin. Conclusion: The activity and reactivity to thrombin of platelets increased in MS patients, and dauricine was able to reduce the occurrence of the irreversible platelet aggregation in MS patients.