Two central pattern generators from the crab Cancer borealis respond robustly and differentially to extreme extracellular pH
Abstract
The activity of neuronal circuits depends on the properties of the constituent neurons and their underlying synaptic and intrinsic currents. We describe the effects of extreme changes in extracellular pH - from pH 5.5 to 10.4 - on two central pattern generating networks, the stomatogastric and cardiac ganglia of the crab, Cancer borealis. Given that the physiological properties of ion channels are known to be sensitive to pH within the range tested, it is surprising that these rhythms generally remained robust from pH 6.1 to pH 8.8. The pH sensitivity of these rhythms was highly variable between animals and, unexpectedly, between ganglia. Animal-to-animal variability was likely a consequence of similar network performance arising from variable sets of underlying conductances. Together, these results illustrate the potential difficulty in generalizing the effects of environmental perturbation across circuits, even within the same animal.
Data availability
Raw .abf data files are available for download at https://doi.org/10.17605/osf.io/r7aes. All code is available for download at github.com/jesshaley/haley_hampton_marder_2019. Source data files have been provided for Figures 2, 3, 4, 6, 7, 8, and their figure supplements.
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Recordings of stomatogastric and cardiac ganglia of C. borealis at varying pHOpen Source Framework, osf.io/r7aes.
Article and author information
Author details
Funding
National Institutes of Health (R35 NS 097343)
- Eve Marder
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Haley 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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