Objective: To observe the effect of Xiaobanxia decoction on the movement of isolated ileum in guinea pig and analyze the mechanism of anti-emetic effect of Xiaobanxia decoction(XBXD). Method: The effects of XBXD(0

0.1

0.25

0.5

1

2.5

5

10

20

40 g·L-1) on ileum spontaneous contraction tension

amplitude and frequency were investigated in organ bath. Emesis-relating agonists acetylcholine (Ach)

histamine (His)

5-hydroxytryptamine (5-HT)

dopamine (DA) were used as tool drugs

the inhibitory effect of XBXD (0

2

5

10 g·L-1) on contraction tension

amplitude and frequency of isolated ileum in guinea pig were observed. Result: XBXD could dose-dependently inhibit ileum spontaneous contractions

reducing the average tension

amplitude

frequency (P<0.05 or P<0.01 vs control). Ach

His and 5-HT could stimulate ileum contraction

enhance the tension

amplitude and frequency. All the three doses (10

5

2 g·L-1) of XBXD could suppress the ileum contraction stimulated by above three tool drugs

significantly reduced the contraction tension

amplitude and frequency (P<0.05 or P<0.01 vs before XBXD or XBXD 0 g·L-1). DA could inhibit the spontaneous contraction

the middle and small dose (5

2 g·L-1) of XBXD could antagonize the inhibitory effect of DA

and enhance the contraction tension

amplitude and frequency (P<0.05 or P<0.01 vs before XBXD or XBXD 0 g·L-1). Conclusion: XBXD can inhibit spontaneous contractile activity of ileum in guinea pig

the mechanism may be related to blocking M

H1

5-HT and D2receptors or directly suppressing ileum smooth muscle. The mechanism of anti-emetic effect of XBXD needs further study.