Exploring the role of dCA1 Serotonin 2A Receptors in a contextually guided of Recognition Memory task in Rats

Episodic memory can be defined as the memory for unique events. The serotonergic system, one of the main neuromodulatory systems in the brain, appears to play a role in it. Despite a clear involvement of hippocampus (HPC) in episodic memory, information regarding the mechanisms and neurotransmitter systems involved are not completed understood. Recognition memory can be defined as the ability to recognize if a particular event or item was previously encountered and is thus considered, a form of episodic memory. The rodent HPC, and the dorsal CA1 (dCA1) region in particular contributes to object recognition memory. Serotonin 5-HT2a receptors (5-HT2aR) are distributed extensively in the brain, including the HPC. To analyze the role of dCA1-5-HT2aR during different phases of the recognition memory we combined stereotaxic infusion of a selective antagonist with behavioral tasks in rats. We found that dCA1-5-HT2aR are required for the consolidation and retrieval of a contextually guided object memory task. These results suggest that HPC 5-HT2aR are involved in recognition memory when contextual information is an important feature of the task.