Introduction: Serotonin (5-HT) is an indoleamine molecule that functions as a neurotransmitter. Dysregulation of 5-HT transmission in the CNS is reported to be related to different psychiatric disorders. A key component of the system is the serotonin transporter (SERT), regulating serotonin availability in the synaptic cleft through reuptake of serotonin. The aim of the experiment was to analyze long-term effects of transient 5-HT depletion on social behavior, anxiety and compulsive behavior. Methods: Mothers has Dams were treated with 200 mg/kg/day of PCPA, vehicle (saline) or were undisturbed at gestational days (E) 12-14. During postanatal days (P) 7, 21 and 42 frequency and duration of ultrasonic vocalizations (USV). At P64 all animals were subjected to 30 min of marble burying test (MB). 24 h after MB, animals underwent 5 min of light/dark box test (LDB). 48 h after last treatment, dissecionsdissections of mPFC and Raphe were obtain in order to analyze mRNA expression of SERT Results: Frequencies of USVs were altered in adolescence. These alterations are not observed during infancy or at weaning. Animals treated with PCPA did not displayed an anxiety-like phenotype, with a downregulation of SERT expression in mPFC. Conclusions: Transient prenatal depletion alters social and anxiety-like behavior during adolescence and young adulthood. This could be linked to a downregulation of SERT in mPFC, that could lead, in turn, to an overexpression of 5-HT in this area, a symptom