Correlating Arc expression with strength of recent versus remote long-term memory for social transmission of food preference in PDE11A WT and KO mice
PDE11A4, which degrades cAMP/cGMP and regulates glutamate signaling and protein synthesis, is preferentially expressed in neurons of CA1, the subiculum, and the adjacently connected amygdalohippocampal region. Deletion of PDE11A enhances remote LTM for social odor recognition and social transmission of food preference (STFP) despite eliminating/silencing recent LTM for those same social events. Here we tested animals on social transmission of food preference and measured Arc mRNA using in situ hybridization. Arc mRNA is a surrogate marker of neuronal activation, and results here suggest the impaired recent LTM for STFP observed in Pde11 KO mice corresponds with decreased activation of ventral CA1 relative to wild-type (WT) littermates, whereas, the enhanced remote LTM for STFP observed in Pde11a KO mice corresponds with increased activation and altered functional connectivity of anterior cingulate cortex, frontal association cortex, parasubiculum, and the superficial layer of medial entorhinal cortex.