Abstract
On the basis of light and electron microscopic observations of the cross-section, the total count of optic nerve fibers in the eastern chipmunk (Tamias Sibiricus asiaticus) was estimated to be 5.65 × 105. Almost all the fibers were myelinated and only 0.9% were unmyelinated. Axon diameters of myelinated fibers showed a skewed unimodal distribution ranging from 0.2 to 3.6 μm (mean, 0.83) with the peak at 0.6-0.7 μm. Myelin sheath thickness positively correlated with the axon diameter. In the cross-section fiber density was highest in the naso-dorsal to the central part and lowest in the temporo-ventral part. Large axons are concentrated in the temporo-ventral part of the optic nerve, corresponding to the localisation of large ganglion cells in temporal crescent of the retina. A gross retinotopic organisation was verified among the optic nerve fibers in the cross-section after localised lesions by laser beam in the nasal and temporal periphery. However, when the retinal lesion was made in or around the central high density area, a non-retinotopic arrangement of the optic nerve fibers was suggested.
| Original language | English |
|---|---|
| Pages (from-to) | 1891-1901 |
| Number of pages | 11 |
| Journal | Vision Research |
| Volume | 27 |
| Issue number | 11 |
| DOIs | |
| Publication status | Published - 1987 |
| Externally published | Yes |
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Keywords
- (Tamias sibiricus asiaticus)
- Axon diameter
- Eastern chipmunk
- Optic nerve
- Retinotopy
- Total fiber count
ASJC Scopus subject areas
- Ophthalmology
- Sensory Systems
Cite this
An electron microscopic analysis of the optic nerve of the eastern chipmunk (Tamias sibiricus asiaticus) : Total fiber count and retinotopic organisation. / Wakakuwa, Kazuo; Watanabe, Masami; Sugimoto, Tomosada; Washida, Asao; Fukuda, Yutaka.
In: Vision Research, Vol. 27, No. 11, 1987, p. 1891-1901.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - An electron microscopic analysis of the optic nerve of the eastern chipmunk (Tamias sibiricus asiaticus)
T2 - Total fiber count and retinotopic organisation
AU - Wakakuwa, Kazuo
AU - Watanabe, Masami
AU - Sugimoto, Tomosada
AU - Washida, Asao
AU - Fukuda, Yutaka
PY - 1987
Y1 - 1987
N2 - On the basis of light and electron microscopic observations of the cross-section, the total count of optic nerve fibers in the eastern chipmunk (Tamias Sibiricus asiaticus) was estimated to be 5.65 × 105. Almost all the fibers were myelinated and only 0.9% were unmyelinated. Axon diameters of myelinated fibers showed a skewed unimodal distribution ranging from 0.2 to 3.6 μm (mean, 0.83) with the peak at 0.6-0.7 μm. Myelin sheath thickness positively correlated with the axon diameter. In the cross-section fiber density was highest in the naso-dorsal to the central part and lowest in the temporo-ventral part. Large axons are concentrated in the temporo-ventral part of the optic nerve, corresponding to the localisation of large ganglion cells in temporal crescent of the retina. A gross retinotopic organisation was verified among the optic nerve fibers in the cross-section after localised lesions by laser beam in the nasal and temporal periphery. However, when the retinal lesion was made in or around the central high density area, a non-retinotopic arrangement of the optic nerve fibers was suggested.
AB - On the basis of light and electron microscopic observations of the cross-section, the total count of optic nerve fibers in the eastern chipmunk (Tamias Sibiricus asiaticus) was estimated to be 5.65 × 105. Almost all the fibers were myelinated and only 0.9% were unmyelinated. Axon diameters of myelinated fibers showed a skewed unimodal distribution ranging from 0.2 to 3.6 μm (mean, 0.83) with the peak at 0.6-0.7 μm. Myelin sheath thickness positively correlated with the axon diameter. In the cross-section fiber density was highest in the naso-dorsal to the central part and lowest in the temporo-ventral part. Large axons are concentrated in the temporo-ventral part of the optic nerve, corresponding to the localisation of large ganglion cells in temporal crescent of the retina. A gross retinotopic organisation was verified among the optic nerve fibers in the cross-section after localised lesions by laser beam in the nasal and temporal periphery. However, when the retinal lesion was made in or around the central high density area, a non-retinotopic arrangement of the optic nerve fibers was suggested.
KW - (Tamias sibiricus asiaticus)
KW - Axon diameter
KW - Eastern chipmunk
KW - Optic nerve
KW - Retinotopy
KW - Total fiber count
UR - http://www.scopus.com/inward/record.url?scp=0023610070&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0023610070&partnerID=8YFLogxK
U2 - 10.1016/0042-6989(87)90055-1
DO - 10.1016/0042-6989(87)90055-1
M3 - Article
C2 - 3447344
AN - SCOPUS:0023610070
VL - 27
SP - 1891
EP - 1901
JO - Vision Research
JF - Vision Research
SN - 0042-6989
IS - 11
ER -