Direct synaptic connections between superior colliculus afferents and thalamo-insular projection neurons in the feline suprageniculate nucleus

A double-labeling study with WGA-HRP and kainic acid

Kaeko Hoshino, Masao Horie, A. Nagy, Antal Berényi, G. Benedek, Masao Norita

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

The suprageniculate nucleus (Sg) of the feline thalamus, which subserves largely unimodal sensory and orientation behavior, receives input from the deep layers of the superior colliculus (SC), and projects to the suprasylvian cortical areas, such as the anterior ectosylvian visual area and the insular visual area (IVA), which contain visually responsive neurons. Through a double tract-tracing procedure involving the injection of wheat germ agglutinin conjugated with horseradish peroxidase (WGA-HRP) into the IVA and the injection of kainic acid into the SC, this study sought to determine the nature of the synaptic relationship between the SC afferents and the thalamo-cortical projection neurons. WGA-HRP injections labeled numerous neurons in the Sg, while kainic acid injections destroyed many tectothalamic terminals in the Sg. The distributions of the WGA-HRP-labeled neurons and the degenerated axon terminals overlapped in the dorsal part of the Sg. Electron microscopic observations demonstrated that the degenerated axon terminals made synaptic contacts with the dendrites of the WGA-HRP-labeled neurons in this overlapping region of the Sg. These results provide the first anatomical evidence that the Sg may play a role in the key relay of visual information from the SC to the IVA, within an identified extrageniculo-cortical pathway.

Original languageEnglish
Pages (from-to)7-13
Number of pages7
JournalNeuroscience Research
Volume66
Issue number1
DOIs
Publication statusPublished - Jan 2010

Fingerprint

Wheat Germ Agglutinins
Superior Colliculi
Kainic Acid
Felidae
Horseradish Peroxidase
Neurons
Injections
Presynaptic Terminals
Dendrites
Thalamus
Electrons

Keywords

  • Degeneration
  • Electron microscopy
  • Extrageniculate visual system
  • Insular visual area
  • Tectum
  • Tracer

ASJC Scopus subject areas

  • Neuroscience(all)

Cite this

@article{12059896617f4a36865c659ad430e813,
title = "Direct synaptic connections between superior colliculus afferents and thalamo-insular projection neurons in the feline suprageniculate nucleus: A double-labeling study with WGA-HRP and kainic acid",
abstract = "The suprageniculate nucleus (Sg) of the feline thalamus, which subserves largely unimodal sensory and orientation behavior, receives input from the deep layers of the superior colliculus (SC), and projects to the suprasylvian cortical areas, such as the anterior ectosylvian visual area and the insular visual area (IVA), which contain visually responsive neurons. Through a double tract-tracing procedure involving the injection of wheat germ agglutinin conjugated with horseradish peroxidase (WGA-HRP) into the IVA and the injection of kainic acid into the SC, this study sought to determine the nature of the synaptic relationship between the SC afferents and the thalamo-cortical projection neurons. WGA-HRP injections labeled numerous neurons in the Sg, while kainic acid injections destroyed many tectothalamic terminals in the Sg. The distributions of the WGA-HRP-labeled neurons and the degenerated axon terminals overlapped in the dorsal part of the Sg. Electron microscopic observations demonstrated that the degenerated axon terminals made synaptic contacts with the dendrites of the WGA-HRP-labeled neurons in this overlapping region of the Sg. These results provide the first anatomical evidence that the Sg may play a role in the key relay of visual information from the SC to the IVA, within an identified extrageniculo-cortical pathway.",
keywords = "Degeneration, Electron microscopy, Extrageniculate visual system, Insular visual area, Tectum, Tracer",
author = "Kaeko Hoshino and Masao Horie and A. Nagy and Antal Ber{\'e}nyi and G. Benedek and Masao Norita",
year = "2010",
month = "1",
doi = "10.1016/j.neures.2009.09.002",
language = "English",
volume = "66",
pages = "7--13",
journal = "Neuroscience Research",
issn = "0168-0102",
publisher = "Elsevier Ireland Ltd",
number = "1",

}

TY - JOUR

T1 - Direct synaptic connections between superior colliculus afferents and thalamo-insular projection neurons in the feline suprageniculate nucleus

T2 - A double-labeling study with WGA-HRP and kainic acid

AU - Hoshino, Kaeko

AU - Horie, Masao

AU - Nagy, A.

AU - Berényi, Antal

AU - Benedek, G.

AU - Norita, Masao

PY - 2010/1

Y1 - 2010/1

N2 - The suprageniculate nucleus (Sg) of the feline thalamus, which subserves largely unimodal sensory and orientation behavior, receives input from the deep layers of the superior colliculus (SC), and projects to the suprasylvian cortical areas, such as the anterior ectosylvian visual area and the insular visual area (IVA), which contain visually responsive neurons. Through a double tract-tracing procedure involving the injection of wheat germ agglutinin conjugated with horseradish peroxidase (WGA-HRP) into the IVA and the injection of kainic acid into the SC, this study sought to determine the nature of the synaptic relationship between the SC afferents and the thalamo-cortical projection neurons. WGA-HRP injections labeled numerous neurons in the Sg, while kainic acid injections destroyed many tectothalamic terminals in the Sg. The distributions of the WGA-HRP-labeled neurons and the degenerated axon terminals overlapped in the dorsal part of the Sg. Electron microscopic observations demonstrated that the degenerated axon terminals made synaptic contacts with the dendrites of the WGA-HRP-labeled neurons in this overlapping region of the Sg. These results provide the first anatomical evidence that the Sg may play a role in the key relay of visual information from the SC to the IVA, within an identified extrageniculo-cortical pathway.

AB - The suprageniculate nucleus (Sg) of the feline thalamus, which subserves largely unimodal sensory and orientation behavior, receives input from the deep layers of the superior colliculus (SC), and projects to the suprasylvian cortical areas, such as the anterior ectosylvian visual area and the insular visual area (IVA), which contain visually responsive neurons. Through a double tract-tracing procedure involving the injection of wheat germ agglutinin conjugated with horseradish peroxidase (WGA-HRP) into the IVA and the injection of kainic acid into the SC, this study sought to determine the nature of the synaptic relationship between the SC afferents and the thalamo-cortical projection neurons. WGA-HRP injections labeled numerous neurons in the Sg, while kainic acid injections destroyed many tectothalamic terminals in the Sg. The distributions of the WGA-HRP-labeled neurons and the degenerated axon terminals overlapped in the dorsal part of the Sg. Electron microscopic observations demonstrated that the degenerated axon terminals made synaptic contacts with the dendrites of the WGA-HRP-labeled neurons in this overlapping region of the Sg. These results provide the first anatomical evidence that the Sg may play a role in the key relay of visual information from the SC to the IVA, within an identified extrageniculo-cortical pathway.

KW - Degeneration

KW - Electron microscopy

KW - Extrageniculate visual system

KW - Insular visual area

KW - Tectum

KW - Tracer

UR - http://www.scopus.com/inward/record.url?scp=73249134938&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=73249134938&partnerID=8YFLogxK

U2 - 10.1016/j.neures.2009.09.002

DO - 10.1016/j.neures.2009.09.002

M3 - Article

VL - 66

SP - 7

EP - 13

JO - Neuroscience Research

JF - Neuroscience Research

SN - 0168-0102

IS - 1

ER -