open access

Vol 82, No 4 (2023)
Original article
Submitted: 2022-01-02
Accepted: 2022-05-03
Published online: 2022-11-29
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Different types of visual cells in the photoreceptor layer of the retinae of the treeshrew (Tupaia belangeri chinensis) as revealed by scanning microscopy

R.S.Y. Cheng1, M.S.M. Wai2, G.C.T. Leung13, T.C.H. Chow13, W.W. Sze-To1, D.T. Yew123
·
Pubmed: 36472397
·
Folia Morphol 2023;82(4):798-804.
Affiliations
  1. School of Chinese Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong
  2. School of Biomedical Science, The Chinese University of Hong Kong, Shatin, Hong Kong
  3. Hong Kong College of Technology, Shatin, Hong Kong

open access

Vol 82, No 4 (2023)
ORIGINAL ARTICLES
Submitted: 2022-01-02
Accepted: 2022-05-03
Published online: 2022-11-29

Abstract

Background: The retinae of treeshrew have never been evaluated by scanning
electron microscopic studies.
Materials and methods: This work described the visual cells in the photoreceptor
layer of the retinae of treeshrew (Tupaia belangeri chinensis) living on the high
plateau of Yunnan, China, via scanning electron microscopy.
Results: Results indicated five morphologically different types of cones, two of
which contain oil droplets in their inner segments. To our knowledge, no prior
studies have reported oil droplets in the visual cells of higher mammals, only in
lower vertebrate and primitive mammals. In addition, this study revealed one type
of degenerative visual cell without outer segments.
Conclusions: The findings signal the needs for additional studies to understand
the physiological functions and phylogenetic relationships of the diversity of visual
cells in this group of mammal.

Abstract

Background: The retinae of treeshrew have never been evaluated by scanning
electron microscopic studies.
Materials and methods: This work described the visual cells in the photoreceptor
layer of the retinae of treeshrew (Tupaia belangeri chinensis) living on the high
plateau of Yunnan, China, via scanning electron microscopy.
Results: Results indicated five morphologically different types of cones, two of
which contain oil droplets in their inner segments. To our knowledge, no prior
studies have reported oil droplets in the visual cells of higher mammals, only in
lower vertebrate and primitive mammals. In addition, this study revealed one type
of degenerative visual cell without outer segments.
Conclusions: The findings signal the needs for additional studies to understand
the physiological functions and phylogenetic relationships of the diversity of visual
cells in this group of mammal.

Get Citation

Keywords

retina, Tupaia belangeri, treeshrew, cones, rods, scanning electron microscopy

About this article
Title

Different types of visual cells in the photoreceptor layer of the retinae of the treeshrew (Tupaia belangeri chinensis) as revealed by scanning microscopy

Journal

Folia Morphologica

Issue

Vol 82, No 4 (2023)

Article type

Original article

Pages

798-804

Published online

2022-11-29

Page views

676

Article views/downloads

407

DOI

10.5603/FM.a2022.0099

Pubmed

36472397

Bibliographic record

Folia Morphol 2023;82(4):798-804.

Keywords

retina
Tupaia belangeri
treeshrew
cones
rods
scanning electron microscopy

Authors

R.S.Y. Cheng
M.S.M. Wai
G.C.T. Leung
T.C.H. Chow
W.W. Sze-To
D.T. Yew

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