Non-invasive central nervous system assessment of a porcine model of neuropathic pain demonstrates increased latency of somatosensory-evoked potentials

David R Hilgart; Marta M Iversen; Angela Y Peters; Matthew S Zabriskie; Guillaume L Hoareau; Natalia Vapniarsky; Gregory A Clark; Lubdha M Shah; Viola Rieke

doi:10.1016/j.jneumeth.2023.109934

Non-invasive central nervous system assessment of a porcine model of neuropathic pain demonstrates increased latency of somatosensory-evoked potentials

J Neurosci Methods. 2023 Aug 1:396:109934. doi: 10.1016/j.jneumeth.2023.109934. Epub 2023 Jul 29.

Authors

David R Hilgart¹, Marta M Iversen², Angela Y Peters³, Matthew S Zabriskie⁴, Guillaume L Hoareau⁵, Natalia Vapniarsky⁶, Gregory A Clark¹, Lubdha M Shah⁴, Viola Rieke⁷

Affiliations

¹ Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, USA.
² Department of Physical Medicine and Rehabilitation, University of Utah, Salt Lake City, UT, USA.
³ Department of Neurology, University of Utah, Salt Lake City, UT, USA.
⁴ Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, UT, USA.
⁵ Department of Emergency Medicine, University of Utah, Salt Lake City, UT, USA.
⁶ Department of Pathology Microbiology and Immunology, University of California Davis, Davis, CA, USA.
⁷ Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, UT, USA. Electronic address: viola.rieke@utah.edu.

PMID: 37524248
PMCID: PMC10530261 (available on 2024-08-01)
DOI: 10.1016/j.jneumeth.2023.109934

Abstract

Background: The study of chronic pain and its treatments requires a robust animal model with objective and quantifiable metrics. Porcine neuropathic pain models have been assessed with peripheral pain recordings and behavioral responses, but thus far central nervous system electrophysiology has not been investigated. This work aimed to record non-invasive, somatosensory-evoked potentials (SEPs) via electroencephalography in order to quantitatively assess chronic neuropathic pain induced in a porcine model.

New method: Peripheral neuritis trauma (PNT) was induced unilaterally in the common peroneal nerve of domestic farm pigs, with the contralateral leg serving as the control for each animal. SEPs were generated by stimulation of the peripheral nerves distal to the PNT and were recorded non-invasively using transcranial electroencephalography (EEG). The P30 wave of the SEP was analyzed for latency changes.

Results: P30 SEPs were successfully recorded with non-invasive EEG. PNT resulted in significantly longer P30 SEP latencies (p < 0.01 [n = 8]) with a median latency increase of 14.3 [IQR 5.0 - 17.5] ms. Histological results confirmed perineural inflammatory response and nerve damage around the PNT nerves.

Comparison with existing method(s): Control P30 SEPs were similar in latency and amplitude to those previously recorded invasively in healthy pigs. Non-invasive recordings have numerous advantages over invasive measures.

Conclusions: P30 SEP latency can serve as a quantifiable neurological measure that reflects central nervous system processing in a porcine model of chronic pain. Advancing the development of a porcine chronic pain model will facilitate the translation of experimental therapies into human clinical trials.

Keywords: Chronic pain; Electroencephalography; Nerve injury; Peripheral neuritis trauma; Pigs; Somatosensory-evoked potentials.

Publication types

Research Support, N.I.H., Extramural

MeSH terms

Animals
Central Nervous System
Chronic Pain*
Electric Stimulation
Electroencephalography
Evoked Potentials, Somatosensory / physiology
Humans
Median Nerve
Neuralgia* / diagnosis
Swine

Grants and funding

UH2 AR076736/AR/NIAMS NIH HHS/United States