CONICET | Buscador de Institutos y Recursos Humanos

Social Cognition encloses a large variety of behaviors and it is a domain commonly affected in psychiatric disorders. Serotonin has been linked to social behavior in humans due to its association with the regulation of mood and aggressive behavior and also due to the use of selective serotonin reuptake inhibitors as the first line of treatment for these disorders. Recently it has become clearer that episodic memory systems can interact with social cognitive processes and that intact memory processing is important to navigate and the social world. Interestingly, the brain areas involved in social cognition significantly overlap with the ones involved in episodic memory. In this work we analyzed if chronic administration of the antidepressant fluoxetine (FLX) affects social cognition and memory processes and a putative role of 5-HT2aR in this effect. For this purpose, we administrated a chronic oral dose of FLX (10 mg/kg) to wild type (WT) and 5-HT2aR knockout mice (KO). After 4 weeks of FLX administration, the animals performed a series of behavioral tasks that include novelty suppressed feeding (NSF), social interaction (SI) and novel object recognition (NOR). We used a NOR task with a 3 min training session that was not enough to generate a long-term NOR memory at 24 h in WT or KO mice. Interestingly, after FLX treatment WT but not KO mice remembered having seen the familiar object during a test performed 24 h after training. We observed no interaction between genotype and treatment when mice were trained to generate a long.term memory. In the social interaction task, chronic FLX increased the exploration time of the social stimuli in WT but not in KO mice. These results suggest that chronic fluoxetine can influence social interaction and episodic like memory and that these effects are at least partially mediated by 5-HT2aR.