Pharmacokinetics of puerarin and ginsenoside Rg1 of CBN injection and the relation with platelet aggregation in rats

In order to study the pharmacokinetics of puerarin and ginsenoside Rg1 of cerebral blood nutrition (CBN) and its relationship with pharmacodynamics of platelet aggregation induced by ADP in rat, the blood samples after injection were collected. The concentrations of puerarin and ginsenoside Rg1 in plasma were determined by RP-HPLC, and the platelet aggregations were observed simultaneously. The data showed that there was distinct statistic significance (p < 0.01) for puerarin processing, which was a single compartment model with quick elimination rate (t(1/2beta) = 18 min) and MRT (26 min), while ginsenoside Rg1 processing was a double compartment model with rapid distribution rate (t(1/2alpha) = 8 min), slow elimination rate (t(1/2beta) = 11 hours) and MRT (3.3 hours). Effects of anti-platelet aggregation were presented at 5-10 min, 45-90 min and 6-8 hours after injection separately, and the corresponding concentrations of puerarin were 25-21 microg/ml, 4.5-0.8 microg/ml and 0 microg/ml, ginsenoside Rg1 were 7.6-6.7 microg/ml, 1.2-0.6 microg/ml and 1.8-0.5 microg/ml. The two components presented a positive correlation between their concentrations and the effect of anti-platelet aggregation in 5-10 min after CBN injection (coefficient of correlation were 0.999 and 0.995). However, it was noted that the effect was still stronger even when concentrations of puerarin and ginsenoside Rg1 in plasma decreased. Therefore, puerarin and ginsenoside Rg1 not only had different pharmacokinetics, but also had a positive correlation with platelet aggregation, just in 5-10 min after CBN injection.