Project description:Gene expression within the prefrontal cortex and amygdala in a developing model of high and low anixety and depression-like behavior in rats
Project description:We carried out untargeted metabolomics of the prefrontal cortex of rats exposed to chronic social isolation (CSIS), a rat model of depression, and/or fluoxetine treatment using liquid chromatography-high resolution mass spectrometry.
Project description:The depressive-like behavior in animals is usually assessed by standardized behavioral tests such as the forced swimming test. However, the findings of these tests may be affected by individual variability among animals, which may hinder the discovery of genes responsible for depression. Few reports have showed the influence of individual variability in identifying the genes associated with depressive-like behavior. In this study, we measured the immobility ratio (% immobility in 5 min) in the forced swimming test in 106 male Wistar rats. According to the distribution of individual immobility ratio, the rats were divided into three groups: the control group with immobility ratio -1 to +1 standard deviation (SD) from the mean, the depressive group with immobility ratio +1 to +2 SD above the mean, and the anti-depressive group with immobility ratio -1 to -2 SD below the mean. Microarray analysis was used to identify the genes differentially expressed by depressive group rats in the prefrontal cortex and cerebellum. The differentially expressed genes in both brain regions of the depressive group were Alas2, Gh1, Hba-a2, Hbb, Hbb-b1, Hbe2, LOC689064, Mrps10, Mybpc, Olf6415, and Pfkb1. Ingenuity pathway analysis identified Gh1 as a hub gene in the networks of the differentially expressed genes in both brain regions. This study indicates that inherent differences in depressive-like behavior may be related to the Gh1 expression in the cerebellum and prefrontal cortex. We measured the immobility ratio of 106 normal rats using the forced swimming test and statistically analysis. We selected the rats exhibitting depressive-like behavior or average in the 106 rats. Total RNA was prepareted from the cerebellum and prefrontal cortex. An equal amount of RNA from 4 rats in each group was pooled and used for microarray analysis.