Mouse hippocampal CA1 VIP interneurons detect novelty in the environment and support recognition memory
Suhel Tamboli,
Sanjay Singh,
Dimitry Topolnik,
Mohamed El Amine Barkat,
Risna Radhakrishnan,
Alexandre Guet-McCreight,
Lisa Topolnik
Affiliations
Suhel Tamboli
Neuroscience Axis, CRCHUQ-CHUL, Quebec City, PQ, Canada; Department of Biochemistry, Microbiology, and Bioinformatics, Université Laval, Quebec City, PQ, Canada
Sanjay Singh
Neuroscience Axis, CRCHUQ-CHUL, Quebec City, PQ, Canada; Department of Biochemistry, Microbiology, and Bioinformatics, Université Laval, Quebec City, PQ, Canada
Dimitry Topolnik
Neuroscience Axis, CRCHUQ-CHUL, Quebec City, PQ, Canada; Department of Biochemistry, Microbiology, and Bioinformatics, Université Laval, Quebec City, PQ, Canada
Mohamed El Amine Barkat
Neuroscience Axis, CRCHUQ-CHUL, Quebec City, PQ, Canada; Department of Biochemistry, Microbiology, and Bioinformatics, Université Laval, Quebec City, PQ, Canada
Risna Radhakrishnan
Neuroscience Axis, CRCHUQ-CHUL, Quebec City, PQ, Canada; Department of Biochemistry, Microbiology, and Bioinformatics, Université Laval, Quebec City, PQ, Canada
Alexandre Guet-McCreight
Krembil Centre for Neuroinformatic, University of Toronto, Toronto, ON, Canada
Lisa Topolnik
Neuroscience Axis, CRCHUQ-CHUL, Quebec City, PQ, Canada; Department of Biochemistry, Microbiology, and Bioinformatics, Université Laval, Quebec City, PQ, Canada; Corresponding author
Summary: In the CA1 hippocampus, vasoactive intestinal polypeptide-expressing interneurons (VIP-INs) play a prominent role in disinhibitory circuit motifs. However, the specific behavioral conditions that lead to circuit disinhibition remain uncertain. To investigate the behavioral relevance of VIP-IN activity, we employed wireless technologies allowing us to monitor and manipulate their function in freely behaving mice. Our findings reveal that, during spatial exploration in new environments, VIP-INs in the CA1 hippocampal region become highly active, facilitating the rapid encoding of novel spatial information. Remarkably, both VIP-INs and pyramidal neurons (PNs) exhibit increased activity when encountering novel changes in the environment, including context- and object-related alterations. Concurrently, somatostatin- and parvalbumin-expressing inhibitory populations show an inverse relationship with VIP-IN and PN activity, revealing circuit disinhibition that occurs on a timescale of seconds. Thus, VIP-IN-mediated disinhibition may constitute a crucial element in the rapid encoding of novelty and the acquisition of recognition memory.
