Evoked responses to single pulse electrical stimulation reveal impaired striatal excitability in a rat model of Parkinson's disease

Copyright © 2023. Published by Elsevier Inc..

BACKGROUND: Sensorimotor beta oscillations are increased in Parkinson's disease (PD) due to the alteration of dopaminergic transmission. This electrophysiological read-out is reported both in patients and in animal models such as the 6-OHDA rat model obtained with unilateral nigral injection of 6-hydroxydopamine (6-OHDA). Current treatments, based on dopaminergic replacement, transiently normalize this pathological beta activity and improve patients' quality of life.

OBJECTIVES: We wanted to assess in vivo whether the abnormal beta oscillations can be correlated with impaired striatal or cortical excitability of the sensorimotor system and modulated by the pharmacological manipulation of the dopaminergic system.

METHODS: In the unilateral 6-OHDA rat model and control animals, we used intra-striatal and intra-cortical single-pulse electrical stimulation (SPES) and concurrent local field potentials (LFP) recordings. In the two groups, we quantified basal cortico-striatal excitability from time-resolved spectral analyses of LFP evoked responses induced remotely by intracerebral stimulations. The temporal dependance of cortico-striatal excitability to dopaminergic transmission was further tested using electrophysiological recordings combined with levodopa injection.

RESULTS: LFP evoked responses after striatal stimulation showed a transient reduction of power in a large time-frequency domain in the 6-OHDA group compared to the sham group. This result was specific to the striatum, as no significant difference was observed in cortical LFP evoked responses between the two groups. This impaired striatal excitability in the 6-OHDA group was observed in the striatum at least during the first 3 months after the initial lesion. In addition, the striatum responses to SPES during a levodopa challenge showed a transient potentiation of the decrease of responsiveness in frequencies below 40 Hz.

CONCLUSION: The spectral properties of striatal responses to SPES show high sensitivity to dopaminergic transmission in the unilateral 6-OHDA rat model. We thus propose that this approach could be used in preclinical models as a time-resolved biomarker of impaired dopaminergic transmission capable of monitoring progressive neurodegeneration and/or challenges to drug intake.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:185

Enthalten in:

Neurobiology of disease - 185(2023) vom: 19. Sept., Seite 106266

Sprache:

Englisch

Beteiligte Personen:

Gronlier, Eloïse [VerfasserIn]
Volle, Julien [VerfasserIn]
Coizet, Véronique [VerfasserIn]
Paccard, Antoine [VerfasserIn]
Habermacher, Chloé [VerfasserIn]
Roche, Yann [VerfasserIn]
Roucard, Corinne [VerfasserIn]
Duveau, Venceslas [VerfasserIn]
David, Olivier [VerfasserIn]

Links:

Volltext

Themen:

46627O600J
6-hydroxydopamine (6-OHDA)
8HW4YBZ748
Brain excitability
Direct electrical stimulation (DES)
Dopamine
Intracranial electroencephalography (iEEG)
Journal Article
Levodopa
Local field potential (LFP)
Oxidopamine
Parkinson's disease
Research Support, Non-U.S. Gov't
Rodent
Single pulse electrical stimulation (SPES)
VTD58H1Z2X

Anmerkungen:

Date Completed 04.09.2023

Date Revised 02.10.2023

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.nbd.2023.106266

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM361029152