Pharmacokinetic study of salvianolic acid D after oral and intravenous administration in rats

Abstract

A sensitive, specific and rapid LC-MS method was developed and validated for the determination of salvianolic acid D (SalD) in rat plasma. This method used a single quadrupole mass spectrometer with an electrospray ionization (ESI) source. A single ion monitoring scanning (SIM) mode was employed. It showed good linearity over the concentration range from 3.3 to 666.7 ng/mL for the determination of SalD. The R.S.D.% of intra-day and inter-day precision values were no more than 7.69%, and the accuracy was within 91%-104% at all quality control levels. This LC-MS method was applied to the pharmacokinetic study of SalD in rats. A two-compartmental model analysis was employed. The plasma concentrations at 2 min (C 2min) were 5756.06±719.61, 11,073.01±1783.46 and 21,077.58±5581.97 μg/L for 0.25, 0.5 and 1 mg/kg intravenous injection, respectively. The peak plasma concentration (C max) was 333.08±61.21 μg/L for 4 mg/kg oral administration. The area under curve (AUC0-t ) was 14,384.379±8443.184, 22,813.369±11,860.823, 46,406.122±27,592.645 and 8201.740±4711.961 μg/L·h for intravenous injection (0.25, 0.5 and 1 mg/kg) and oral administration (4 mg/kg), respectively. The bioavailability of SalD was calculated to be 4.159%±0.517%.

Keywords: AUC, the area under curve; Analysis method; Bioavailability; CI, confidence interval; CL, clearance; Cmax, peak plasma concentration; Danshen; Dose proportionality; ECE-1, endothelin converting enzyme 1; ESI, electrospray ionization; IS, internal standard; LC-MS; LLOQ, lower limit of quantification; Pharmacokinetics; QC, quality control; R.E., relative error; R.S.D., relative standard deviation; SIM, single ion monitoring; SalB, salvianolic acid B; SalD, salvianolic acid D; Salvia miltiorrhiza; Salvianolic acid D; TCM, traditional Chinese medicine; ULOQ, upper limit of quantification.

Graphical abstract

Figure 1

Chemical structures of SalD and naringin.

Figure 2

Full scan of SalD and IS: (A) SalD and (B) IS.

Figure 3

Typical chromatograms of SalD and IS (A) blank rat plasma; (B) blank rat plasma spiked with SalD and IS; and (C) rat plasma sample at 1 h after intravenous injection of SalD spiked with IS.

Figure 4

Mean plasma concentration-time curves of SalD. (A) Mean plasma concentration-time curves of rats (i.v., n=6); (B) semi-logarithmic axis mean plasma concentration-time curves of rats (i.v., n=6); (C) mean plasma concentration-time curves of rats with 4 mg/kg dose (p.o., n=6).

Figure 5

Relationship between lnPK and lnDose. The dashed lines are the 90% confidence intervals. (A) AUC_0−t; (B) AUC_0−∞; and (C) C_2min.