Serotonin Type 2a Receptor in the Prefrontal Cortex Controls Perirhinal Cortex Excitability During Object Recognition Memory Recall. (10th August 2022)

• Record Type: Journal Article
• Authors: Morici, J.F.; Cicuttin, G.; Silva, A.; Gallo, F.T.; Miranda, M.; Belluscio, M.; Zold, C.; Bekinschtein, P.; Weisstaub, N.V.
• Is Part Of: Neuroscience. Volume 497(2022)
• Page Start: 196
• Page End: 205
• Publication Date: 2022-08-10
• Subjects: serotonin 2aR -- recognition memory -- medial Prefrontal Cortex -- Perirhinal Cortex -- c-Fos; Neurochemistry -- Periodicals; Neurophysiology -- Periodicals; Neurology -- Periodicals; Neurochimie -- Périodiques; Neurophysiologie -- Périodiques; Neurochemistry; Neurophysiology; Electronic journals; Periodicals; Electronic journals; 612.8
• DOI: 10.1016/j.neuroscience.2022.05.015
• Languages: English
• ISSNs: 0306-4522

Abstract

Highlights: c-fos expression increase during the retrieval phase of the OIC in the PRH and PFC Pharmacological blockade of mPFC 5-HT2aR increase c-fos expression during the solution of the OIC in the anterior and posterior regions of the PRH. c-fos expression in the PRH inversely correlates with the behavioral response observed during the test phase of the OIC. Blockade of Prefrontal 5-HT2aR increase c-fos expression in this structure. Abstract: Previous experiences can drive adaptive behavior based on different characteristics, including contextual ones. Indeed, contextual information can be used as a criterion to guide the recall of the most relevant memory trace and the inhibition of others. The medial Prefontal Cortex (mPFC) has been proposed as an area that plays a pivotal role in regulating the retrieval of memory traces in downstream regions. Also, we have shown that mPFC Serotonin 2a Receptors (5-HT2aR) modulates the retrieval of a contextually guided recognition memory task and modulates the retrieval and reconsolidation of memories in the Perirhinal Cortex (PRH). However, how the mPFC output mediated by the 5-HT2aR activity is modulating memory retrieval in the PRH is a question that remains unclear. To tackle this question, we analyzed neuronal activity in the PRH and mPFC, by measuring expression of the immediate early gene c-Fos. We combined behavioral, pharmacological and immunohistochemical techniques to examine how mPFC 5-HT2aR controls mPFC and the PRH activity. We found that blockade of mPFC 5-HT2aR increase the level of c-Fos expression in the PHR and that this increase correlates with animals' performance in the task. We also found an increase in c-Fos expression in the mPFC after mPFC 5-HT2aR blockade that does not correlate with the animals' behavioral response. However, these changes showed a significant correlation with those observed in the PRH. These results suggest that mPFC 5-HT2aR signaling may modulate the behavioral response during memory recall by controlling the neuronal activation in the PRH.