Novel long-range inhibitory nNOS-expressing hippocampal cells
Abstract
The hippocampus, a brain region important for spatial navigation and episodic memory, benefits from a rich diversity of neuronal cell-types. Through the use of an intersectional genetic viral vector approach in mice, we report novel hippocampal neurons which we refer to as LINCs, as they are long-range inhibitory neuronal nitric oxide synthase (nNOS)-expressing cells. LINCs project to several extrahippocampal regions including the tenia tecta, diagonal band, and retromammillary nucleus, but also broadly target local CA1 cells. LINCs are thus both interneurons and projection neurons. LINCs display regular spiking non-pyramidal firing patterns, are primarily located in the stratum oriens or pyramidale, have sparsely spiny dendrites, and do not typically express somatostatin, VIP, or the muscarinic acetylcholine receptor M2. We further demonstrate that LINCs can strongly influence hippocampal function and oscillations, including interregional coherence. Identification and characterization of these novel cells advances our basic understanding of both hippocampal circuitry and neuronal diversity.
Data availability
All data used for analysis in this publication are included in the manuscript and supporting files. Source data has been included for Table 1. Custom MatLab code is available through GitHub, Inc. at https://github.com/KM-Lab/SpectrumAndCoherence.
Article and author information
Author details
Funding
National Institutes of Health (R01-NS104071)
- Esther Krook-Magnuson
National Institutes of Health (F31-NS105457)
- Zoé Christenson Wick
University of Minnesota (MnDRIVE (Minnesota's Discovery Research and Innovation Economy) initiative)
- Zoé Christenson Wick
- Esther Krook-Magnuson
University of Minnesota (McKnight Land-Grant Professorship)
- Esther Krook-Magnuson
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All experimental protocols were performed in strict accordance with and approved by the University of Minnesota's Institutional Animal Care and Use Committee (protocol # 1801-35497A).
Copyright
© 2019, Christenson Wick et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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