Dye coupling of horizontal cells in the primate retina
In the monkey retina, there are two distinct types of axon-bearing horizontal cells, known as H1 and H2 horizontal cells (HCs). In this study, cell bodies were prelabled using 4′,6-diamidino-2-phenylindole (DAPI), and both H1 and H2 horizontal cells were filled with Neurobiotin™ to reveal their coup...
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| Format: | Article |
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Frontiers Media S.A.
2023-11-01
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| Series: | Frontiers in Ophthalmology |
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| Online Access: | https://www.frontiersin.org/articles/10.3389/fopht.2023.1173706/full |
| _version_ | 1797623051402084352 |
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| author | Feng Pan Feng Pan Feng Pan Stephen C. Massey |
| author_facet | Feng Pan Feng Pan Feng Pan Stephen C. Massey |
| author_sort | Feng Pan |
| collection | DOAJ |
| description | In the monkey retina, there are two distinct types of axon-bearing horizontal cells, known as H1 and H2 horizontal cells (HCs). In this study, cell bodies were prelabled using 4′,6-diamidino-2-phenylindole (DAPI), and both H1 and H2 horizontal cells were filled with Neurobiotin™ to reveal their coupling, cellular details, and photoreceptor contacts. The confocal analysis of H1 and H2 HCs was used to assess the colocalization of terminal dendrites with glutamate receptors at cone pedicles. After filling H1 somas, a large coupled mosaic of H1 cells was labeled. The dendritic terminals of H1 cells contacted red/green cone pedicles, with the occasional sparse contact with blue cone pedicles observed. The H2 cells were also dye-coupled. They had larger dendritic fields and lower densities. The dendritic terminals of H2 cells preferentially contacted blue cone pedicles, but additional contacts with nearly all cones within the dendritic field were still observed. The red/green cones constitute 99% of the input to H1 HCs, whereas H2 HCs receive a more balanced input, which is composed of 58% red/green cones and 42% blue cones. These observations confirm those made in earlier studies on primate horizontal cells by Dacey and Goodchild in 1996. Both H1 and H2 HCs were axon-bearing. H1 axon terminals (H1 ATs) were independently coupled and contacted rod spherules exclusively. In contrast, the H2 axon terminals contacted cones, with some preference for blue cone pedicles, as reported by Chan and Grünert in 1998. The primate retina contains three independently coupled HC networks in the outer plexiform layer (OPL), identified as H1 and H2 somatic dendrites, and H1 ATs. At each cone pedicle, the colocalization of both H1 and H2 dendritic tips with GluA4 subunits close to the cone synaptic ribbons indicates that glutamate signaling from the cones to H1 and H2 horizontal cells is mediated by α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors. |
| first_indexed | 2024-03-11T09:18:58Z |
| format | Article |
| id | doaj.art-6d61b2ff69644aae867b06565865d6f8 |
| institution | Directory Open Access Journal |
| issn | 2674-0826 |
| language | English |
| last_indexed | 2024-03-11T09:18:58Z |
| publishDate | 2023-11-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Ophthalmology |
| spelling | doaj.art-6d61b2ff69644aae867b06565865d6f82023-11-16T18:26:30ZengFrontiers Media S.A.Frontiers in Ophthalmology2674-08262023-11-01310.3389/fopht.2023.11737061173706Dye coupling of horizontal cells in the primate retinaFeng Pan0Feng Pan1Feng Pan2Stephen C. Massey3School of Optometry, The Hong Kong Polytechnic University, Hong Kong, Hong Kong SAR, ChinaCentre for Eye and Vision Research (CEVR), Hong Kong, Hong Kong SAR, ChinaResearch Centre for SHARP Vision (RCSV), The Hong Kong Polytechnic University, Hong Kong, Hong Kong SAR, ChinaRuiz Department of Ophthalmology and Visual Science, McGovern Medical School, University of Texas at Houston, Houston, TX, United StatesIn the monkey retina, there are two distinct types of axon-bearing horizontal cells, known as H1 and H2 horizontal cells (HCs). In this study, cell bodies were prelabled using 4′,6-diamidino-2-phenylindole (DAPI), and both H1 and H2 horizontal cells were filled with Neurobiotin™ to reveal their coupling, cellular details, and photoreceptor contacts. The confocal analysis of H1 and H2 HCs was used to assess the colocalization of terminal dendrites with glutamate receptors at cone pedicles. After filling H1 somas, a large coupled mosaic of H1 cells was labeled. The dendritic terminals of H1 cells contacted red/green cone pedicles, with the occasional sparse contact with blue cone pedicles observed. The H2 cells were also dye-coupled. They had larger dendritic fields and lower densities. The dendritic terminals of H2 cells preferentially contacted blue cone pedicles, but additional contacts with nearly all cones within the dendritic field were still observed. The red/green cones constitute 99% of the input to H1 HCs, whereas H2 HCs receive a more balanced input, which is composed of 58% red/green cones and 42% blue cones. These observations confirm those made in earlier studies on primate horizontal cells by Dacey and Goodchild in 1996. Both H1 and H2 HCs were axon-bearing. H1 axon terminals (H1 ATs) were independently coupled and contacted rod spherules exclusively. In contrast, the H2 axon terminals contacted cones, with some preference for blue cone pedicles, as reported by Chan and Grünert in 1998. The primate retina contains three independently coupled HC networks in the outer plexiform layer (OPL), identified as H1 and H2 somatic dendrites, and H1 ATs. At each cone pedicle, the colocalization of both H1 and H2 dendritic tips with GluA4 subunits close to the cone synaptic ribbons indicates that glutamate signaling from the cones to H1 and H2 horizontal cells is mediated by α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors.https://www.frontiersin.org/articles/10.3389/fopht.2023.1173706/fullhorizontal cellsretinagap junctionglutamate receptorsphotoreceptors |
| spellingShingle | Feng Pan Feng Pan Feng Pan Stephen C. Massey Dye coupling of horizontal cells in the primate retina Frontiers in Ophthalmology horizontal cells retina gap junction glutamate receptors photoreceptors |
| title | Dye coupling of horizontal cells in the primate retina |
| title_full | Dye coupling of horizontal cells in the primate retina |
| title_fullStr | Dye coupling of horizontal cells in the primate retina |
| title_full_unstemmed | Dye coupling of horizontal cells in the primate retina |
| title_short | Dye coupling of horizontal cells in the primate retina |
| title_sort | dye coupling of horizontal cells in the primate retina |
| topic | horizontal cells retina gap junction glutamate receptors photoreceptors |
| url | https://www.frontiersin.org/articles/10.3389/fopht.2023.1173706/full |
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