Objective: To study the effect of Chaihu Shugan San (CHSGS) on serum motilin (MOT) and interstitial cells of Cajal-deep muscular plexus (ICC-DMP) in model rats with liver depression syndrome. Method: All 50 SD rats were randomly divided into 5 groups:normal group

model group

the high and low dose groups of CHSGS(21.0

10.5 g·kg-1

ig)

and domperidone group (10 mg·kg-1

ig)

10 rats in each group. The rats in rest 4 groups except normal group received modeling for 3 weeks by chronic unpredicted mild stress (CUMS). In the next 2 weeks after stimulus

each group was treated with gavage intervention daily 10 mL·kg-1. The normal and the model group received ig normal saline(NS) of the same volume. The changes of weight and ethological indexes of immobility time in forced swimming test were observed before and after the administration of CHSGS. Serum MOT levels were detected by using enzyme linked immunosorbent assay (ELISA)

and ICC-DMP changes were observed under electron microscopy. Result: Compared with the normal group

the rats in model group had an obvious weight loss after modeling;immobility time was prolonged (P<0.05);serum MOT levels were decreased (P<0.05). After administration

compared with model group

CHSGS could reduce the immobility time in forced swimming test (P<0.05)

significantly increase serum MOT levels (P<0.05)

and significantly improve the structure and function of ICC-DMP under electron microscope. Conclusion: CHSGS has the effect of promoting gastrointestinal motility

and the mechanism may be associated with regulating serum MOT levels

as well as quantity and function of ICC-DMP in rats with liver depression syndrome.