Synaptic modulation of glutamate in striatum of the YAC128 mouse model of Huntington disease

Bibliographic Details
Title: Synaptic modulation of glutamate in striatum of the YAC128 mouse model of Huntington disease
Authors: Judy Cheng, Ellen T. Koch, Daniel Ramandi, James P. Mackay, Timothy P. O’Leary, William Rees-Jones, Lynn A. Raymond
Source: Neurobiology of Disease, Vol 205, Iss , Pp 106774- (2025)
Publisher Information: Elsevier, 2025.
Publication Year: 2025
Collection: LCC:Neurosciences. Biological psychiatry. Neuropsychiatry
Subject Terms: Huntington disease, Striatum, Corticostriatal synapse, Glutamate, Dopamine, Endocannabinoids, Neurosciences. Biological psychiatry. Neuropsychiatry, RC321-571
More Details: Background: Altered balance between striatal direct and indirect pathways contributes to early motor, cognitive and psychiatric symptoms in Huntington disease (HD). While degeneration of striatal D2-type dopamine receptor (D2)-expressing indirect pathway medium spiny neurons (iMSNs) occurs prior to that of D1-type dopamine receptor (D1)-expressing direct pathway neurons, altered corticostriatal synaptic function precedes degeneration. D2-mediated signaling on iMSNs reduces their excitability and promotes endocannabinoid (eCB) synthesis, suppressing glutamate release from cortical afferents. D2 receptors are also expressed on glutamatergic cortical terminals, cholinergic interneurons, and dopaminergic terminals from substantia nigra where they suppress release of glutamate, acetylcholine and dopamine, respectively, and these cell types may contribute to early striatal dysfunction in HD. Thus, we used corticostriatal brain slices and optogenetic probes to directly investigate neuromodulatory signaling in the transgenic YAC128 HD mouse model. Results: Low-dose D2 agonist quinpirole reduced cortically-evoked glutamate release in dorsal striatum of premanifest YAC128 slices but not WT, and blocking type 1 cannabinoid receptors mitigated this effect. YAC128 corticostriatal brain slices also showed increased evoked dopamine and reduced evoked eCB release compared to WT, while acetylcholine signaling patterns remained relatively intact. Conclusions: These findings suggest that YAC128 corticostriatal slices show increased D2 sensitivity that is eCB-dependent, and that dopamine and eCB release are altered at an early disease stage. We provide evidence for impaired neuromodulatory signaling in early HD, guiding therapeutic efforts prior to the onset of overt motor symptoms later on.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 1095-953X
Relation: http://www.sciencedirect.com/science/article/pii/S0969996124003760; https://doaj.org/toc/1095-953X
DOI: 10.1016/j.nbd.2024.106774
Access URL: https://doaj.org/article/233e64ef5d1a4c0ba1ec9175cdecb636
Accession Number: edsdoj.233e64ef5d1a4c0ba1ec9175cdecb636
Database: Directory of Open Access Journals
More Details
ISSN:1095953X
DOI:10.1016/j.nbd.2024.106774
Published in:Neurobiology of Disease
Language:English