SLC6A4 and major depressive disorder: The present study aimed to evaluate the short- (mid-adolescence) and long-term (early adulthood) effects of the CSD model during early adolescence on behaviors like depression, the SERT density in the prefrontal cortex (PFC) and hippocampus, the visuospatial learning and memory, and the serum levels of corticosterone and testosterone, in male mice of the Swiss Webster (SW) strain.