Study on the Role of Expression in the Dentate Gyrus of the Hippocampus in Reward Memory.

Objective: Emotional memory has been associated with many psychiatric diseases. Understanding emotional memory could be beneficial in comprehending and discovering new therapies for diseases related to emotional memory, such as depression and post-traumatic stress disorder (PTSD). Our previous study revealed that expression in the dentate gyrus (DG) contributes to fear memory. However, is there a correlation between expression in the DG and reward memory? This study aims to explore the relationship between expression and reward memory.

Methods: We induced fear memory (Fear group) or reward memory (Reward group) using fear conditioning and social interaction in females, respectively. We then measured the expression levels of and after the retrieval of different types of memory. Additionally, we used a recombinant Adeno-Associated Virus (rAAV) to overexpress in the DG and conducted conditioned place preference (CPP) tests to assess changes in reward memory.

Results: We observed a significant increase in and expression in the Fear group compared with the Reward group. Overexpression of in the DG led to an increase in time spent in the white box during CPP tests.

Conclusion: expression levels varied after the retrieval of fear or reward memory, and overexpression of in the DG enhanced reward memory. These findings suggest that expression in the DG plays a role in reward memory.