Study on the Activity of Anti-platelet Aggregation of Dendrobium Chrysotoxum in Vitro

OBJECTIVE To screen for the anti-platelet aggregation activity of Dendrobium chrysotoxum extract, and discuss its antithrombotic effect. METHODS Fifteen rats were randomly divided into Dendrobium chrysotoxum extract 1 (gc1) group, Dendrobium chrysotoxum extract 2 (gc2) group, Dendrobium chrysotoxum extract 3 (gc3) group, Dendrobium chrysotoxum extract 4 (gc4) group and the positive control group of aspirin, 3 per group. While 15 guinea pigs were randomly divided into 5 groups, 3 per group. Platelet aggregation was induced by adenosine triphosphate (ADP) in vitro in rats and arachidonic acid (AA) in vitro in guinea pigs. The maximal aggregation rate of platelet-rich plasma of the blank group, Dendrobium chrysotoxum extracts from different concentrations and the positive control group of aspirin as detected in 5 min. The inhibition rate of platelet aggregation and the half inhibitory concentration (IC50) of each subject were calculated. RESULTS Compared with the normal control group, the maximal aggregation rate induced by ADP of gc1 (5.318 mmol·L^-1), gc2 (1.708 mmol·L^-1), gc3 (2.925 mmol·L^-1), gc4 (3.152, 1.576, 0.394 mmol·L^-1) groups significantly decreased (P<0.05 or P<0.01). Compared with the normal control group, the maximal aggregation rate induced by AA of gc1 (0.083, 0.166 mmol·L^-1), gc2 (0.106, 0.214 mmol·L^-1), gc3 (0.023 mmol·L^-1), gc4 (0.049, 0.099, 0.197, 0.394 mmol·L^-1) groups significantly decreased (P<0.05 or P<0.01). CONCLUSION There are many kinds of ingredients in Dendrobium chrysotoxum which have anti-platelet aggregation activity. Dendrobium chrysotoxum has positive effects on thrombotic diseases.