Academic Journal

Laminar segregation of excitatory and inhibitory projections from the inferior colliculus to the superior colliculus.

Λεπτομέρειες βιβλιογραφικής εγγραφής
Τίτλος: Laminar segregation of excitatory and inhibitory projections from the inferior colliculus to the superior colliculus.
Συγγραφείς: Saqib KA; Systems Function and Morphology Laboratory, Graduate School of Innovative Life Science, University of Toyama, Toyama 930-0194 Japan., Takahashi K; Systems Function and Morphology Laboratory, Graduate School of Innovative Life Science, University of Toyama, Toyama 930-0194 Japan; Research Center for Idling Brain Science, University of Toyama, Toyama 930-0194 Japan., Hase K; Systems Function and Morphology Laboratory, Graduate School of Innovative Life Science, University of Toyama, Toyama 930-0194 Japan; Research Center for Idling Brain Science, University of Toyama, Toyama 930-0194 Japan., Miyajima T; Systems Function and Morphology Laboratory, Graduate School of Innovative Life Science, University of Toyama, Toyama 930-0194 Japan., Yamamoto M; Systems Function and Morphology Laboratory, Graduate School of Innovative Life Science, University of Toyama, Toyama 930-0194 Japan., Yamamoto R; Department of Physiology, School of Medicine, Kanazawa Medical University, Ishikawa, Japan., Takahashi M; Center for Genomic and Regenerative Medicine, Juntendo University Graduate School of Medicine, Tokyo, Japan; Department of Neuroanatomy, Juntendo University Graduate School of Medicine, Tokyo, Japan., Hioki H; Department of Neuroanatomy, Juntendo University Graduate School of Medicine, Tokyo, Japan; Department of Multi-Scale Brain Structure Imaging, Juntendo University Graduate School of Medicine, Tokyo, Japan; Department of Cell Biology and Neuroscience, Juntendo University Graduate School of Medicine, Tokyo, Japan., Ito T; Systems Function and Morphology Laboratory, Graduate School of Innovative Life Science, University of Toyama, Toyama 930-0194 Japan; Research Center for Idling Brain Science, University of Toyama, Toyama 930-0194 Japan. Electronic address: itot@med.u-toyama.ac.jp.
Πηγή: Hearing research [Hear Res] 2026 Aug; Vol. 478, pp. 109692. Date of Electronic Publication: 2026 May 30.
Τύπος έκδοσης: Journal Article; Research Support, Non-U.S. Gov't
Γλώσσα: English
Στοιχεία περιοδικού: Publisher: Elsevier/North-Holland Biomedical Press Country of Publication: Netherlands NLM ID: 7900445 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 1878-5891 (Electronic) Linking ISSN: 03785955 NLM ISO Abbreviation: Hear Res Subsets: MEDLINE
Imprint Name(s): Original Publication: Amsterdam, Elsevier/North-Holland Biomedical Press.
Ιατρικοί όροι (MeSH): Inferior Colliculi*/physiology , Inferior Colliculi*/metabolism , Superior Colliculi*/physiology , Superior Colliculi*/metabolism , Auditory Pathways*/physiology , Auditory Pathways*/metabolism , Neural Inhibition*, Vesicular Glutamate Transport Protein 2/genetics ; Vesicular Glutamate Transport Protein 2/metabolism ; Glutamate Decarboxylase/genetics ; Glutamate Decarboxylase/metabolism ; Amino Acid Transport Systems, Acidic/genetics ; Amino Acid Transport Systems, Acidic/metabolism ; RNA, Messenger/metabolism ; Brain Mapping/methods ; Animals ; Mice, Transgenic ; Mice, Inbred C57BL ; Neuroanatomical Tract-Tracing Techniques ; Female ; Male ; Mice
Περίληψη: The superior colliculus (SC) integrates multimodal spatial information to guide orientation behaviors. Visual inputs to superficial layers drive these behaviors through circuits in deeper layers, which also receive input from other sensory modalities. The inferior colliculus (IC), a central midbrain hub of auditory system, provides both VGluT2-expressing excitatory and VGAT/GAD67-expressing inhibitory projections to the SC, but the organization of these projections remains incompletely understood. In this study, we systematically mapped excitatory and inhibitory IC projections to the SC. Cre-dependent viral tracing in VGluT2-Cre and VGAT-Cre mice was used to label excitatory and inhibitory IC axons, respectively. In addition, retrograde tracing combined with fluorescent in situ hybridization for VGluT2 and GAD67 mRNAs was used to identify IC neurons projecting to the superficial SC layers, deeper SC layers, or medial geniculate body (MGB). Both excitatory and inhibitory IC projections innervated superficial and deep SC layers; however, inhibitory projections showed a modest bias toward superficial layers, whereas excitatory projections preferentially targeted deeper layers. Retrograde tracing further revealed that SC-projecting inhibitory neurons were located more frequently in rostral shell subdivisions. The proportion of inhibitory projection neurons was higher for superficial SC than for deep SC and MGB. These findings reveal a structural organization of IC projections to the SC that differs from the classical IC-MGB auditory pathway and suggest a circuit mechanism through which auditory signals may modulate visual processing in the SC.
(Copyright © 2026 The Author(s). Published by Elsevier B.V. All rights reserved.)
Competing Interests: Declaration of interest The authors declare no competing interests.
Contributed Indexing: Keywords: Excitatory-inhibitory balance; Inferior colliculus; Laminar circuitry; Multisensory integration; Superior colliculus
Substance Nomenclature: 0 (Vesicular Glutamate Transport Protein 2)
EC 4.1.1.15 (Glutamate Decarboxylase)
EC 4.1.1.15 (glutamate decarboxylase 1)
0 (Slc17a6 protein, mouse)
0 (Amino Acid Transport Systems, Acidic)
0 (RNA, Messenger)
Entry Date(s): Date Created: 20260613 Date Completed: 20260701 Latest Revision: 20260807
Update Code: 20260808
DOI: 10.1016/j.heares.2026.109692
PMID: 42287970
Βάση Δεδομένων: MEDLINE