Therefore, considering that hippocampus is critical for stress, learning, and memory processes in depression and in the antidepressant response to pharmacotherapy [22–24], the aim of the present study was to evaluate the effects of daily nobiletin treatment on sucrose preference and corresponding changes in BDNF, TrkB receptor, and the downstream target synapsin I in the hippocampus after CUMS. This evidence concerns the gene BDNF and major depressive disorder.