What is the true discharge rate and pattern of the striatal projection neurons in Parkinson's disease and Dystonia?
Abstract
Dopamine and striatal dysfunctions play a key role in the pathophysiology of Parkinson's disease (PD) and Dystonia, but our understanding of the changes in the discharge rate and pattern of striatal projection neurons (SPNs) remains limited. Here, we recorded and examined multi-unit signals from the striatum of PD and dystonic patients undergoing deep brain stimulation surgeries. Contrary to earlier human findings, we found no drastic changes in the spontaneous discharge of the well-isolated and stationary SPNs of the PD patients compared to the dystonic patients or to the normal levels of striatal activity reported in healthy animals. Moreover, cluster analysis using SPN discharge properties did not characterize two well-separated SPN subpopulations, indicating no SPN subpopulation-specific (D1 or D2 SPNs) discharge alterations in the pathological state. Our results imply that small to moderate changes in spontaneous SPN discharge related to PD and Dystonia are likely amplified by basal ganglia downstream structures.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 2, 3 and 9.
Article and author information
Author details
Funding
European Research Council
- Hagai Bergman
Rosetrees
- Hagai Bergman
Israel Science Foundation
- Hagai Bergman
Israel Authority for Innovation
- Hagai Bergman
French National Research Agency
- Marc Deffains
French National Center for Scientific Research
- Marc Deffains
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Aryn H Gittis, Carnegie Mellon University, United States
Ethics
Human subjects: All patients met the criteria for DBS and signed a written informed consent for surgery that involved microelectrode recording. This study was authorized and approved by the Institutional Review Board of Hadassah Hospital in accordance with the Helsinki Declaration (reference code: 0168-10-HMO)
Version history
- Received: March 31, 2020
- Accepted: August 14, 2020
- Accepted Manuscript published: August 19, 2020 (version 1)
- Version of Record published: September 1, 2020 (version 2)
Copyright
© 2020, Valsky 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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