Sini Power（SP） is a famed traditional Chinese formula that has long been used to treat depression. Here, we investigated the effects and possible mechanisms of SP extract on an established model of depression： chronic stressed tree shrew, which mimics the human condition of social stress. The animals were divided into 4 groups. Except for the na？ve group, the other animals were subjected to daily social defeat stress for 5 weeks, and during the last 4 weeks treated with SP extract（3.6 g/kg/d）, fluoxetine（15 mg/kg/d）, and vehicle, respectively. The results showed that SP extract could reverse body weight loss to a certain extent and reduce the levels of urine/serum cortisol that were initially increased by chronic social defeat. In addition, SP extract increased hippocampus norepinephrine concentrations. Our data suggested that SP extract had positive effects on the main depression symptoms in the chronic stressed tree shrew model and that it may be used to help control hypothalamic-pituitary-adrenal axis hyperactivity.
