The sex difference under non-stressed and chronic-stressed conditions in C57BL/6 mice

Animal models are important tools in scientific research, whereas the animals used are usually single-sex instead of mixed-sex in the experimental design. To better understand the effect of sex difference, we compared several phenotypes between male and female C57BL/6 mice, including behavioral tests, plasma corticosterone levels, adult neurogenesis, and RNA-seq. The experiments were performed under non-stressed and chronic-stressed conditions, respectively. Overall, our results showed several differences between male and female mice in sensorimotor performance while little difference was found in anxiety, depression, learning, and memory. We did not observe a significant difference in adult neurogenesis. There was a sex difference in plasma corticosterone levels under chronic stress conditions, either in 30 min after the restraint stress or after 60min of the recovery. Yet, the corticosterone levels were equivalent between the sexes under non-stressed conditions at any time point. Furthermore, the results of RNA-seq identified the differential expression genes between male and female mice under non-stressed or chronic-stressed conditions. Comparative gene expression profiling analysis of RNA-seq data for the hippocampus from C57BL/6 mice under non-stressed and chronic-stressed conditions.