To investigate the regulatory effects of Chaihu Shugan Powder（柴胡疏肝散）on the adenylate-activated protein activating enzyme（AMPK）/mammalian target of rapamycin（mTOR）/UNC-51-like kinase 1（ULK1）pathway and glial cells in the orbitofrontal cortex（OFC）of depression model rats.

The rat model of depression was established by chronic unpredictable mild stress（CUMS）.According to the random number table，10 rats were selected as the normal group and 50 rats with successful modeling were divided into model group，escitalopram group（10.50 mg/kg），Chaihu Shugan Powder lowdose group（3.15 g/kg），Chaihu Shugan Powder middle-dose group（6.30 g/kg），Chaihu Shugan Powder high-dose group（12.60 g/kg）according to the random number table，with ten rats in each group for 28 consecutive days.The changes of sugar preference coefficient，suspension immobility time and open field walking distance of rats in each group were observed.After the above detection was completed，the head was decapitated and the brain was removed，and the expressions of ionized calciumbinding receptor molecule 1（Iba-1），myelin basic protein（MBP）and glial fibrillary acidic protein（GFAP）in rat OFC tissues were detected by immunofluorescence assay.Western blotting method was used to detect the protein expressions of pT172-AMPK/AMPK，pS2488-mTOR/mTOR and pS757-ULK1/ULK1 in OFC tissue.The expressions of AMPK，mTOR and ULK1 mRNA in OFC were detected by real-time PCR.

Compared to the control group，the model group and each treatment group showed a decrease in sucrose preference coefficient，an increase in immobility time in the forced swimming test and a decrease in distance traveled in the open field test（P<0.05，P<0.01）.Compared to the model group，each treatment group showed an increase in sucrose preference coefficient，a decrease in immobility time and an increase in distance traveled in the open field test（P<0.01）.Compared to the control group，the model group and each treatment group showed an increase in protein expressions of Iba-1 and GFAP（P<0.05，P<0.01），and a decrease in MBP protein expression（P<0.01），except those in the Chaihu Shugan Powder low-dose group.Compared to the model group，each treatment group showed a decrease in protein expressions of Iba-1 and GFAP（P<0.01），and an increase in MBP protein expression（P<0.01）.Compared to the control group，the model group and each treatment group showed a decrease in protein expressions of pT172-AMPK/AMPK，pS2448-mTOR/mTOR and pS757-ULK1/ULK1（P<0.05，P<0.01）.Compared to the model group，each treatment group showed an increase in protein expressions of pT172-AMPK/AMPK，pS2448-mTOR/mTOR and pS757-ULK1/ULK1（P<0.05）.Compared to the control group，the model group，escitalopram group，Chaihu Shugan Powder low-dose group and middle-dose group showed a decrease in expressions of mTOR and ULK1 mRNA（P<0.01），Chaihu Shugan Powder low-dose group showed a decrease in AMPK mRNA expression（P<0.05），and the Chaihu Shugan Powder high-dose group group showed a decrease in mTOR mRNA expression（P<0.01）.Compared to the model group，each treatment group showed an increase in expressions of AMPK mRNA，mTOR mRNA nd ULK1 mRNA（P<0.01）.

Chaihu Shugan Powder can reduce the expressions of Iba-1 and GFAP in OFC of rats，increase the expression of MBPand activate AMPK/mTOR/ULK1 pathway expression to exert the antidepressant effect.