OBJECTIVETo develop a RP-HPLC method for the determination of the concentration of hydroxysafflor yellow A in rat plasma, to study the pharmacokinetics of Carthamus tinctorius extration and Naodesheng tablet, and to investigate the effect of other components on the pharmacokinetics of hydroxysafflor yellow A.

METHODThe rats were orally treated with Carthamus tinctorius extration and Naodesheng capsule respectively. Blood samples were collected in heparinized eppendorf tube via the oculi chorioideae vein. Plasma was separated by centrifugation at 10 000 r x min(-1) for 10 min, and two-times methanol in volume was added to deposit proteins. After centrifugation, the upper liquid was transferred to filter. The concentration of hydroxysafflor yellow A in serum was determined by RP-HPLC. The stationary phase was C18, and methanol-acetonitrile-0.7% orthophosphoric acid (26: 2:72) was taken as the mobile phase, A UV detector was used at 403 nm. The pharmacokinetic parameters were calculated with 3p97 program.

RESULTA good linear relationship of hydroxysafflor yellow A was obtained in the range of 0.03 and 2.56 mg x L(-1), the lowest limit of determination was 10 microg x L(-1), and the lowest limit of quantitation was 30 microg x L(-1). The mean recoveries were (99.3 +/- 1.4)%, (92.8 +/- 1.8)%, (98.4 +/- 2.0)% for high, middle, low concentrations of the samples respectively. The plasma concentration-time curves of hydroxysafflor yellow A were fitted with two-compartments model. The AUC)0-t), AUC(0-infinity), C(max) and T(max) of hydroxysafflor yellow A were increased in the Naodesheng group, compared with 50 mg x kg(-1) C. tinctorius extract group.

CONCLUSIONThe HPLC method was selective, accurate and sensitive. The results indicated that the other herbs improved the absorption of hydroxysafflor yellow A and increased the bioavailability of hydroxysafflor yellow A significantly.