Effect of Radix and Rhizome on the Pharmacokinetics of Puerarin from Tongmai Granules in Rats

OBJECTIVE To study the influence of the compatibility of radix and rhizome with pueraria on the pharmacokinetics of puerarin in rats.METHODS The blood samples were collected at different time points after oral administration of the extracts from pueraria and compound recipe of pueraria(equivalent to 300 mg.kg-1 puerarin) to Wistar rats respectively,then purified and chromatographic analyzed for the content of puerarin.RESULTS The mean plasma concentration-time curves of puerarin after oral administration of the extracts from pueraria and compound recipe of pueraria were fitted to two compartment open model.There were somewhat difference in the major pharmacokinetic parameters.The pharmacokinetic parameters of the group treated with the extract of pueraria were as follows: t1/2(ka)(9.48±3.94) min,t1/2α(13.74±3.67) min,t1/2β=(136.65±26.00)min,t(peak)(29.02±11.94)min,ρmax(0.90±0.26)mg.L-1,AUC(186.10±49.57)mg.min.L-1,CL/F(s)(1.72±0.53)L.kg-1.min-1,V/F(c)(241.57±94.64)L.kg-1.The pharmacokinetic parameters of the group treated with the extract of compound recipe of pueraria were as follows: t1/2ka(11.12±2.78)min,t1/2α(27.65±7.06)min,t1/2β(610.34±293.58)min,t(peak)(24.50±4.56)min,ρmax(2.57±1.34)mg.L-1,AUC=(571.64±504.22) mg.min.L-1,CL/F(s)(0.84±0.55)L.kg-1.min-1,V/F(c)=(79.45±38.23) L.kg-1.CONCLUSION The work proved that the compatibility of radix and rhizome with pueraria can promote the absorption,increase the blood drug concentration and prolong the action time of puerarin in vivo.