[Effects of Ganmai Dazao Tang on synaptic structure of hippocampal neurons in depression model rats].

To investigate the effects of Ganmai Dazao Tang on behavior and monoamine neurotransmitters in rats with depression, and to explore its potential mechanism from synaptic structure. Sixty SD rats were randomly divided into 5 groups: normal control group, model group, fluoxetine group (10.8 mg/kg), Ganmai Dazao Tang high and low dose group (9.72, 4.86 g/kg), 12 rats in each group. Except the control group, the rats in the other groups were all chronically unpredictable mild stress (CUMS) to establish a depression model, and were treated by intragastric administration for 21 days. The depression-like behaviors of rats were evaluated by sucrose consumption test and open field test. The contents of serotonin (5-HT) and norepinephrine (NE) in hippocampus were detected by ELISA. The synaptic damage of neurons was observed by Golgi staining. The synaptic structure protein expression levels of MAP-2 and GAP-43 of hippocampus were detected by Immunohistochemistry and Western blot. Compared with control group, the sucrose preference and autonomic activity scores of the depression model rats were decreased significantly (＜0.01), the levels of 5-HT and NE in hippocampus were decreased significantly (＜0.01), and the dendritic spines were absent, and the expressions of MAP-2 and GAP-43 were down-regulated significantly (＜0.01). After treated with Ganmai Dazao Tang, the depression-like behavior of the model rats was significantly relieved (＜0.01), and the levels of 5-HT and NE were increased (＜ 0.05). Dendritic spine density, length and branching were increased, the expressions of MAP-2 and GAP-43 were increased (＜ 0.01). Ganmai Dazao Tang can improve the depression-like behavior of depression model rats and increase the monoamine neurotransmitter content in hippocampus, which may be related to up-regulation of synaptic structural proteins and relief of synaptic damage in neurons.