Multi-channel analysis and comparison on absorption difference between paeoniflorin and Paeonia lactiflora extracts

OBJECTIVE: To compare the difference of the absorption difference between paeoniflorin monomer and Paeonia lactiflora extracts in rat intestinal canals by multi-channels. METHOD: The rat intestinal perfusion model was established. The intestinal perfusate, bile and plasma samples were collected, in combination of the intestinal enzymes incubation test and the partition coefficient determination, to conduct a multi-channel analysis and comparison on absorption difference between paeoniflorin and P. lactiflora extracts. RESULT: In the same concentration, permeability coefficient P(eff)* of paeoniflorin in the different intestinal segments of P. lactiflora extract higher than the monomer of paeoniflorin, especially in the jejunum and ileum intestinal segments (P < 0. 05). However, both paeoniflorin monomer and P. lactiflora extracts showed less P(eff)* in four intestinal segments, with the former ranging between 0. 209-0.290 and the latter 0.252-0.333. No paeoniflorin and its metabolin was determined in bile samples, plasma samples and intestinal enzymes incubation samples of paeoniflorin monomer and P. lactiflora extracts. CONCLUSION: Compared with the paeoniflorin monomer, P. lactiflora extract showed significantly increase in P(eff)*, which indicated that other ingredients in the extract can improve the absorption of paeoniflorin. However, due to the poor absorption of paeoniflorin, this effect fails to increase the concentration of paeoniflorin in bile and plasma within short period of time.