Exposure to single prolonged stress fails to induce anxiety-like behavior in mice

Single prolonged stress (SPS) is a well-established and most frequently used rat model to induce post-traumatic stress disorder (PTSD)-like symptoms, which helps to understand the neurobiological mechanisms as well as developing novel therapeutic strategies for PTSD. However, whether such stress model works efficiently in mice remains unknown. In the present study, we established a mouse SPS (mSPS) model by exposing C57BL/6J mice to a series of multimodal stressors on a single day, then the anxiety-like behavior was measured by open-field test, elevated plus maze test, dark-light box, and novelty-suppressed feeding test. Our results showed that mSPS had no significant effect on the anxiety-like behavior in mice after different days of recovery. The expression of the glucocorticoid receptor and brain-derived neurotrophic factor (BDNF), two proteins that highly associated with stress-related behaviors, also remained unaltered in both the amygdala and hippocampus. By contrast, the protein levels of NR2A and NR2B, two main subunits of the N-methyl-D-aspartate receptor (NMDAR), was reduced in the hippocampus, but not amygdala. In conclusion, our results indicate that mSPS may not be an efficient mouse model to explore the pathophysiology of PTSD-related anxiety-like behavior.