Effects of Veratrum nigrum var. ussuriense alkaloids on platelet aggregation and time of coagulation and bleeding / 中草药

ABSTRACT

Object To study the effects of Veratrum nigrum L. var. ussuriense Nakai alkaloids (VnA) on platelet aggregation in rats and coagulation time, bleeding time in mice. Methods The antiplatelet effect of VnA was examined by determining platelet aggregation rate in normal rats and blood stasis model rats by turbidimetric method developed by Born. Whole blood coagulation time (CT) in mice was measured by capillary glass tube method, bleeding time (BT) by hemorrhagic transection of mouse tail model. Results VnA (45, 30, and 15 ?g/kg, iv) significantly inhibited ADP-induced platelet aggregation in rats in a dose-dependent manner. VnA (12.5, 25, 50, and 100 ?g/kg, ip) markedly increased CT and BT in mice. VnA [49.3 ?g/kg, which was anticoagulantly equieffective to heparin (1.25 mg/kg), ip] prolonged BT. There was no statistically significant difference in BT between VnA and heparin, although BT increase induced by VnA was shorter than that induced by heparin. Conclusion VnA has significant antiplatelet effect in rats and can prolong CT and BT in mice. At equieffective dose VnA-induced BT increase does not exceed that heparin induced.