Objective To study the changes in the contents of 5hydroxytryptamine（5-HT） and 5-hydroxyindoleacetic acid（5-HIAA） of the dorsal raphe nucleus（DRN） of rats after acupuncture at Shenmen（HT 7） and Mingmen（GV 4） to discuss the mechanism of acupuncture treatment for insomnia.Methods Eighteen SD male rats were randomized into control group

acupuncture Shenmen（HT 7） group and acupuncture Mingmen（GV 4） group

with 6 in each.A microdialyzer probe was placed into the DRN with stereotaxic technique.The extracellular fluid of DRN 40min before acupuncture and 20

40

60

80

100

and 120min after acupuncture was collected by microdialysis

and the changes in 5-HT and 5-HIAA contents were determined with high performance liquid chromatography-electrochemical detection（HPLC-ED）.Results Compared with before acupuncture

the content of 5-HT of DRN was significantly decreased 20min after acupuncture at Shenmen（HT 7） and Mingmen（GV 4）（P<0.01）

and thereafter it remained low within 2 hours.Compared with the control group

the content of 5-HT of acupuncture groups 2h after acupuncture at each time point was also significantly decreased（P<0.01）.Compared with the basic value before acupuncture and with the control group

acupuncture at Shenmen（HT 7） and Mingmen（GV 4） both could decrease the content of 5-HIAA of DRN（P<0.05）.Conclusion Acupuncture at Shenmen（HT 7） and Mingmen（GV 4） functions to regulate sleep through regulating the contents of 5-HT and 5-HIAA in the tissues of DRN.