Cellular and circuit organization of the locus coeruleus of adult mice
- Baylor College of Medicine, United States
- University of Houston, United States
Abstract
The locus coeruleus (LC) houses the vast majority of noradrenergic neurons in the brain and regulates many fundamental functions including fight and flight response, attention control, and sleep/wake cycles. While efferent projections of the LC have been extensively investigated, little is known about its local circuit organization. Here, we performed large-scale multi-patch recordings of noradrenergic neurons in adult mouse LC to profile their morpho-electric properties while simultaneously examining their interactions. LC noradrenergic neurons are diverse and could be classified into two major morpho-electric types. While fast excitatory synaptic transmission among LC noradrenergic neurons was not observed in our preparation, these mature LC neurons connected via gap junction at a rate similar to their early developmental stage and comparable to other brain regions. Most electrical connections form between dendrites and are restricted to narrowly spaced pairs or small clusters of neurons of the same type. In addition, more than two electrically coupled cell pairs were often identified across a cohort of neurons from individual multi-cell recording sets that followed a chain-like organizational pattern. The assembly of LC noradrenergic neurons thus follows a spatial and cell type-specific wiring principle that may be imposed by a unique chain-like rule.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting files. The data and custom codes supporting the findings are being deposited in Dryad (doi:10.5061/dryad.kh1893283)
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Cellular composition and circuit organization of mouse locus coeruleusDryad Digital Repository, doi:10.5061/dryad.kh1893283.
Article and author information
Author details
Funding
Eunice Kennedy Shriver National Institute of Child Health and Human Development (P50HD103555)
- Andrew McKinney
- Ming Hu
- Junzhan Jing
- Xiaolong Jiang
National Eye Institute (T32 EY07001)
- Andrew McKinney
National Institute of Mental Health (MH109556)
- Ming Hu
- Junzhan Jing
- Xiaolong Jiang
National Institute of Neurological Disorders and Stroke (NS101596)
- Andrew McKinney
- Ming Hu
- Xiaolong Jiang
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2023, McKinney 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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Cellular and circuit organization of the locus coeruleus of adult mice
eLife 12:e80100.
https://doi.org/10.7554/eLife.80100
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