Objective: To study the influence of Polygalae Radix compatibility with Magnoliae Officinalis Cortex to the chemical composition in rats gastrointestinal liquid and plasma. Method: Treating plasma with methanol protein precipitation

the residues were analyzed with HPLC system (Synergi Hydro-RP C18 column

4.6 mm×250 mm

5 μm)

with the mobile phase consisted of acetonitrile-water (51: 49)

flow-rate of 1 mL·min-1

detected-wavelength of 294 nm

and column temperature of 30 ℃. Result: Magnolol and honokiol were detected in both of the Magnoliae Officinails Cortex group and the campatibility group's rats gastric intestinal juice and plasma

and the content of honokiol kind material in campatibility group's rats of gastric juice was obviously higher than the other group at every time piont. The content in rat's intestinal juice was higher than the magnoliae officinails group's rats after ig 150-480 minutes. There are only honokiol which had been detected in the rat's plasma

and the content of it in compatibility group's plasma was much higher than the other group after ig 60-480 minutes

with the trending of delayed absorption. Conclusion: After the compatibility of Polygala and Magnoliae Officinails Cortex

magnolol and honokiol were increased significantly in Magnolia

which may be relevanted with Magnolia relieving Polygala inhibition of gastrointestinal motility. First adopted this method to study the mechanism of Magnolia relieving Polygala inhibition of gastrointestinal motility

which had some innovation significance.