[Water soluble contents of Chinese drug beimu, the bulbs of Fritillaria plants].

Based on platelet aggregation induced by platelet activating factor (PAF), the active fraction with inhibiting effect was screened from four species of Chinese drung Beimu, the bulbs of Fritillaria przewalskii, F. ussurienis, F. anhuiensis and F. thunbergii. According to the experimental results, the active water soluble fraction of F. ussuriensis was further studied. Two nucleosides, thymidine and adenosine were isolated. Platelet aggregation assay shows that adenosine is the chief aggregation inhibitor with 1% = 42 at 5 microns. It is suggested that nucleosides may be the other type of active constituent besides alkaloids in the Fritillaria plants.