Disordered breathing in a mouse model of Dravet syndrome
Abstract
Dravet syndrome (DS) is a form of epilepsy with a high incidence of sudden unexpected death in epilepsy (SUDEP). Respiratory failure is a leading cause of SUDEP, and DS patients' frequently exhibit disordered breathing. Despite this, mechanisms underlying respiratory dysfunction in DS are unknown. We found that mice expressing a DS-associated Scn1a missense mutation (A1783V) conditionally in inhibitory neurons (Slc32a1cre/+::Scn1aA1783V fl/+; defined as Scn1aΔE26) exhibit spontaneous seizures, die prematurely and present a respiratory phenotype including hypoventilation, apnea, and a diminished ventilatory response to CO2. At the cellular level in the retrotrapezoid nucleus (RTN), we found inhibitory neurons expressing the Scn1a A1783V variant are less excitable, whereas glutamatergic chemosensitive RTN neurons, which are a key source of the CO2/H+-dependent drive to breathe, are hyper-excitable in slices from Scn1aΔE26 mice. These results show loss of Scn1a function can disrupt respiratory control at the cellular and whole animal levels.
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We have included source data files for all summary figures that do not include individual data points.
Article and author information
Author details
Funding
National Institutes of Health (HL104101)
- Daniel K Mulkey
Dravet Syndrome Foundation (AG180243)
- Daniel K Mulkey
American Epilepsy Society
- Fu-Shan Kuo
National Institutes of Health (NS104999)
- Joseph L LoTurco
National Institutes of Health (HL142227)
- Colin M Cleary
National Institutes of Health (HL137094)
- Daniel K Mulkey
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Jan-Marino Ramirez, Seattle Children's Research Institute and University of Washington, United States
Ethics
Animal experimentation: All animal use was in accordance with guidelines approved by the University of Connecticut Institutional Animal Care and Use Committee. (Protocols A16-034 and A17-002).
Version history
- Received: November 5, 2018
- Accepted: April 25, 2019
- Accepted Manuscript published: April 26, 2019 (version 1)
- Version of Record published: May 8, 2019 (version 2)
Copyright
© 2019, Kuo 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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