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To screen microRNAs with specific expression of in hippocampus of rats with chronic stress induced depression model, and observe the effect of traditional Chinese medicine Chaihu Shugan San on the expression of microRNA in hippocampus.SD rats were randomly divided into 3 groups: the normal control group, the model control group and the Chaihu Shugan San group. The depression model was replicated by unpredictable chronic mild stress combined with separation. Behavioral changes of the rats were observed by Open-field test and sucrose solution consumption test, and the expression of microRNAs in hippocampus was assayed by microRNA micro-array.Compared with the normal control group, there were 13 specific miRNAs in hippocampus in the model control group with the expression difference of more than 2 times. Among them, down-regulating miRNAs included miR298, miR-130b, miR-135a, miR-323, miR-503, miR-15b, miR-532, and miR-125a, and the up-regulation miRNAs included miR7a, miR-212, miR-124, miR-139, and miR-182. Among the 13 specific miRNAs, miR-125a and miR-182 recovered to normal after intervention with Chaihu Shugan San in the Chaihu Shugan San group.This study preliminarily found that 13 specific miRNAs in hippocampus are related to depression. Among them, miR-125a and miR-182 recover to normal after intervention with Chaihu Shugan San, which may be the target points of the antidepressant effect of Chaihu Shugan San. We shall further analyze the target genes and their mechanisms.

To study the effect of Tiantai No. 1 [symbol in text] on gene expression profile in hippocampus of Alzheimer's disease (AD) rat, molecular genetic target points of the effect of this drug were defined, its molecular genetic pharmacodynamic mechanism of anti-AD was further explored at molecular gene level, and a scientific basis was provided for its clinical availability and promotion.Thirty male Sprague-Dawley rats were divided into three groups with 10 rats per group: sham-operation group, model group and Tiantai No. 1 group. Sterile surgical procedure was applied, the model group with bilateral hippocampal injection of Aβ1-40 was established, and normal saline was used instead of Aβ1-40 in the sham-operation group. One week after the models was made, rats were administered by gastric lavage once every day for three consecutive weeks. The rats of the sham-operation group and the model group were daily fed with purified water by lavage; the rats of the Tiantai No.1 group treated group were administered with Tiantai No.1 by lavage. Total RNAs of hippocampus tissues were extracted with Trizol, the changes of hippocampus gene expression profiles in the above three groups were analyzed by using Affymetrix rat whole genome expression profile microarray.Microarray analysis showed that, compared with the sham-operation group, the hippocampus of the model group had 50 up-regulated genes with significant difference (fold change2), and 21 down-regulated genes with significant difference (fold change0.5); compared with the hippocampus of the model group, the hippocampus of the Tiantai No. 1 group was found to have 5 up-regulated genes with significant difference (fold change2) and 20 down-regulated genes with significant difference (fold change0.5). The functions of differentially expressed genes of the groups were involved in nervous system's development, neuronic differentiation and function-regulation, cellular growth and differentiation and apoptosis, synaptic occurrence and plasticity, inflammation and immune response, ion channels/transporters, cellular signal transduction, cellular material/energy metabolism and so on.Tiantai No. 1 can regulate hippocampal function, and further regulate the brain function of animals in multiple gene target points by a number of ways.

To investigate the effect of Baisong tablets on the nerve-biochemistry and neuroendocrine of chronic mild unpredicted stress depression in rats.Sixty male Sprague-Dawley rats were randomly allocated to 4 groups: a normal control (NC), a model control (MC), a fluoxetine control (FC) and a Baisong tablet treatment group (BST). All rats except the control group were singly housed and exposed to an unpredicted sequence of mild stressor. The levels of serotonin (5-HT), glutamate (Glu) and gama-aminobutyric acid (GABA) of the hippocampus were measured by high-performance liquid chromatography. The concentration of corticotropin releasing hormone (CRH), adrenocorticotropic hormone (ACTH) and cortisol (CORT) in the plasma of the rats were detected by radio-immunity. The CRHmRNA expressions in the hypothalamus and prefrontal cortex were semiquantified by RT-PCR method. The differences of BDNF and TrkB protein expression in CA1 and CA3 pyramidal and dentate gyrus granule cells layers of hippocampus were investigated with immunohistochemistry technique.In comparison with NC group, the levels of 5-HT, and GABA of the hippocampus in MC rats reduced significantly (P0.01), and the concentration of CRH, ACTH, and CORT of the plasma and the level of Glu of the hippocampus and CRH mRNA expression in the brain increased significantly. Fluoxetine or Baisong could significantly regulate the abnormal changes of all the above.Chronic mild unpredicted stress can affect neuroendoerine and cause depression, and Baisong tablet has antagonism against it.

To investigate the effects of Baisong tablet on the behaviors and CRHmRNA expression in the chronic stress rats.Rats were exposed to different ways of chronic stress. Body weight and behaviors were investigated during the whole procedure, the CRHmRNA expressions in the hypothalamus and prefrontal cortex were semiquantified by the RT-PCR method.In comparision with the normal group, rats exposed to chronic stress showed decreased body weight and a significant reduction of consumption of sucrose solution, and the duration of immobility during the forced swimming test was increased significantly. The chronic stress rats was in depression of behavior. CRHmRNA expression in the brain of the chronic stress rats was upregulated significantly, while it was downregulated in the groups of Baisong tablet and the group of fluoxetin.Baisong tablet has the effect of antidepressant, and it may be related to the effect of the downregulated CRHmRNA expression in brain.