Anatomical basis and physiological role of cerebrospinal fluid transport through the murine cribriform plate
Abstract
Cerebrospinal fluid (CSF) flows through the brain, transporting chemical signals and removing waste. CSF production in the brain is balanced by a constant outflow of CSF, the anatomical basis of which is poorly understood. Here we characterized the anatomy and physiological function of the CSF outflow pathway along the olfactory sensory nerves through the cribriform plate, and into the nasal epithelia. Chemical ablation of olfactory sensory nerves greatly reduced outflow of CSF through the cribriform plate. The reduction in CSF outflow did not cause an increase in intracranial pressure (ICP), consistent with an alteration in the pattern of CSF drainage or production. Our results suggest that damage to olfactory sensory neurons (such as from air pollution) could contribute to altered CSF turnover and flow, providing a potential mechanism for neurological diseases.
Data availability
All raw data is plotted in the figures. ICP data and code (Figure 10) is included in a .zip file. Code for the analysis of actograms is available here: https://github.com/DrewLab/MedAssociates_WheelActivity
Article and author information
Author details
Funding
National Science Foundation (CBET1705854)
- Patrick J Drew
National Institutes of Health (F31NS105461)
- Jordan N Norwood
McKnight Endowment Fund for Neuroscience
- Patrick J Drew
National Institutes of Health (R01NS078168)
- Patrick J Drew
National Institutes of Health (P01HD078233)
- Patrick J Drew
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: The protocols used in this study were approved by the Institutional Animal Care and Use Committee (IACUC) at the Pennsylvania State University
Copyright
© 2019, Norwood 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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