Objective: To investigate the regulatory effects of deoxyschizandrin on the function of intestinal smooth muscle in mice and rats

and provide pharmacological basis for revealing the mechanism of ‘astringent efficacy’ of deoxyschizandrin and its effective substance. Method: The 50 Kunming mice were divided into 5 groups according to the balanced random group

normal group

deoxyschizandrin high

medium and low dose groups (20

40

80 mg·kg-1)

and belladonna positive group (20 mg·kg-1). Another 60 Kunming mice were taken and divided into 6 groups according to the balanced random group

normal group

model group (ip

neostigmine)

deoxyschizandrin high

medium

and low dose groups (80

40

20 mg·kg-1)

belladonna positive group (20 mg·kg-1). Corresponding drugs were given by ig

while the normal group and model group were given with distilled water at the same volume

1 time a day

for 5 days. Charcoal propulsion method was respectively used to observe the effect of deoxyschizandrin on intestine propulsion in normal mice and mice models with neostigmine. With the isolated small intestine of rats incubated in cuhk's fluid as the model

the effect of deoxyschizandrin on contractility of isolated intestine smooth muscles in rats was observed. 30 SD rats were randomly divided into normal group

deoxyschizandrin high

medium and low dose groups (80

40

20 mg·kg-1). All the other groups except normal group used folium sennae to prepare diarrhea rat models. After successful modeling

corresponding drugs were given by ig

1 time a day

for 7 days. The effect of deoxyschizandrin on myosin light-chain kinase (MLCK) expressions in intestinal smooth muscles of diarrhea model rats was observed. Result: Compared with normal group and neostigmine group

deoxyschizandrin high dose group and middle dose group could significantly decrease the percentage of carbon powder propulsion in small intestine (P<0.05

P<0.01). 10-80 μmol·L-1 deoxyschizandrin inhibited the contraction of isolated small intestinal smooth muscle in vitro of rats. Compared with senna model group

deoxyschizandrin high

middle and low dose groups could significantly inhibit MLCK expressions in intestinal smooth muscles of diarrhea model rats (P<0.01). Conclusion: Deoxyschizandrin shows the inhibitory effects on the small intestinal movement in vivo mice and in vitro rats

and the mechanism may be associated with inhibiting the expression of MLCK related to intestinal contraction.