OBJECTIVE: To explore the effects of Valerian on the level of 5-hydroxytryptamine (5-HT), cell proliferation and neuron number in cerebral hippocampus of rats with depression induced by chronic mild stress. METHODS: Seventy rats were divided into 7 groups: normal control, untreated, negative control, positive control, and low-, medium- and high-dose Valerian-treated groups. There were 10 rats in each group. Except for the normal control group, depression was induced in rats by chronic mild stress. The depressive rats in the other six groups were intragastrically administered with sodium carboxymethycellulose, fluoxetine, and low, medium and high-dose Valerian, respectively for 3 weeks. After the treatment, the proliferating cells in the hippocampus were labeled by injecting bromodeoxyuridine (BrdU) in 7 groups. The content of 5-hydroxytryptamine (5-HT) in the hippocampus was detected by high-performance liquid chromatography (HPLC), and the number of hippocampal neurons was counted by morphometry. RESULTS: Compared with the normal control group, the levels of 5-HT in the hippocampus in the low- and medium-dose Valerian-treated groups were increased and recovered to normal level. After the administration of low-dose Valerian for 3 weeks, the number of BrdU positive cells and neurons in the hippocampus of the depressive rats were recovered to the normal status. CONCLUSION: Minidose Valerian may promote the level of 5-HT and cell proliferation in the hippocampus of the depressive rats, and may play a role in saving injured neurons of the hippocampus.

OBJECTIVE: To explore the effects of Rhodiola rosea on the body weight and the intake of sucrose and water in depressive rats induced by chronic mild stress.dz METHODS: A total of 70 male SD rats were divided into seven groups, including normal control group (treated with 0.5% sodium carboxymethycellulose), untreated group, negative control group (treated with 0.5% sodium carboxymethycellulose), positive control group (treated with fluoxetine), low-, medium- and high-dose Rhodiola rosea group (treated with 1.5, 3, 6 g/kg Rhodiola rosea respectively). Except for rats in normal control group, the other sixty rats endured chronic stress for 4 weeks to establish the depression model. After that, rats were administered Rhodiola rosea for 3 weeks. During the whole experiment, the body weight, and sucrose intake, tap water intake of all rats were examined once a week. RESULTS: After the termination of the stress regime, compared with the normal control group, the body weight and 1% sucrose intake in depressive rats were decreased. After 3-week Rhodiola rosea treatment, the body weight and 1% sucrose intake increased in rats of the low-dose Rhodiola rosea group and recovered to the level of the normal control group. CONCLUSION: Low-dose Rhodiola rosea can increase the body weight and sucrose intake of depressive rats, making them recover to normal status.