File Download
There are no files associated with this item.
Supplementary
- Citations:
- Appears in Collections:
Article: A morphometric study of optic axons regenerated in a sciatic nerve graft of adult rats
Title | A morphometric study of optic axons regenerated in a sciatic nerve graft of adult rats |
---|---|
Authors | |
Keywords | Axon-glial interaction g-ratio Microtubules Neurofilaments Optic nerve Regenerated optic axons Schwann cells |
Issue Date | 2000 |
Publisher | IOS Press. The Journal's web site is located at http://www.iospress.nl/html/09226028.php |
Citation | Restorative Neurology And Neuroscience, 2000, v. 16 n. 2, p. 105-116 How to Cite? |
Abstract | Purpose: In the present study we have morphometrically examined a regeneration model in which axons normally residing in CNS have regrown and are interacting with Schwann cells from the PNS. This study will not only provide morphometric data on regenerated optic fibers but also shed light on possible factors in determining the fiber morphometry. Methods: The optic nerves of rats aged 6 weeks were cut intra-orbitally and replaced with a autologous sciatic nerve. After a survival period of 9 months, the graft or 'regenerated' nerves containing the regenerated optic axons and Schwann cells were processed for morphometric measurements. Results: The mean myelinated axon diameter of regenerated nerve (1.8 ±0.2 μm) was significantly (P < 0.05) greater than that of the optic nerve (0.9 ± 0.03 μm). However, unmyelinated regenerated optic axons had a smaller mean axon diameter (0.49 ± 0.04 μm) than normal myelinated optic axons. This may suggest that myelinating glial cells exert an influence on axon caliber and Schwann cells seem to have greater effect than oligodendrocytes. The mean g-ratio showing the relative myelin sheath thickness was found to be the highest in the optic nerve (0.78 ± 0.003), least in the sciatic nerve (0.6 ± 0.009) and intermediate in the regenerated nerve (0.68 ± 0.01). The results indicated that Schwann cells myelinating the regenerated optic axons have produced a thinner myelin sheath. Intra-axonally, no significant difference was detected in the number of axonal microtubules and neurofilaments between the regenerated and optic nerves. Therefore the disposition of microtubules and neurofilaments into axon may be intrinsically determined. Conclusions: In this study, we have identified some of the extrinsic and intrinsic factors in determining the fiber morphometry of the regenerated nerve. The axon-size and myelination by glial cells were determined through the external axon-glial interactions, whereas the number of axonal microtubules and neurofilaments were intrinsically determined. |
Persistent Identifier | http://hdl.handle.net/10722/67779 |
ISSN | 2023 Impact Factor: 1.9 2023 SCImago Journal Rankings: 0.612 |
DC Field | Value | Language |
---|---|---|
dc.contributor.author | Wai Kei Chau | en_HK |
dc.contributor.author | So, KF | en_HK |
dc.contributor.author | Tay, D | en_HK |
dc.contributor.author | Dockery, P | en_HK |
dc.date.accessioned | 2010-09-06T05:58:10Z | - |
dc.date.available | 2010-09-06T05:58:10Z | - |
dc.date.issued | 2000 | en_HK |
dc.identifier.citation | Restorative Neurology And Neuroscience, 2000, v. 16 n. 2, p. 105-116 | en_HK |
dc.identifier.issn | 0922-6028 | en_HK |
dc.identifier.uri | http://hdl.handle.net/10722/67779 | - |
dc.description.abstract | Purpose: In the present study we have morphometrically examined a regeneration model in which axons normally residing in CNS have regrown and are interacting with Schwann cells from the PNS. This study will not only provide morphometric data on regenerated optic fibers but also shed light on possible factors in determining the fiber morphometry. Methods: The optic nerves of rats aged 6 weeks were cut intra-orbitally and replaced with a autologous sciatic nerve. After a survival period of 9 months, the graft or 'regenerated' nerves containing the regenerated optic axons and Schwann cells were processed for morphometric measurements. Results: The mean myelinated axon diameter of regenerated nerve (1.8 ±0.2 μm) was significantly (P < 0.05) greater than that of the optic nerve (0.9 ± 0.03 μm). However, unmyelinated regenerated optic axons had a smaller mean axon diameter (0.49 ± 0.04 μm) than normal myelinated optic axons. This may suggest that myelinating glial cells exert an influence on axon caliber and Schwann cells seem to have greater effect than oligodendrocytes. The mean g-ratio showing the relative myelin sheath thickness was found to be the highest in the optic nerve (0.78 ± 0.003), least in the sciatic nerve (0.6 ± 0.009) and intermediate in the regenerated nerve (0.68 ± 0.01). The results indicated that Schwann cells myelinating the regenerated optic axons have produced a thinner myelin sheath. Intra-axonally, no significant difference was detected in the number of axonal microtubules and neurofilaments between the regenerated and optic nerves. Therefore the disposition of microtubules and neurofilaments into axon may be intrinsically determined. Conclusions: In this study, we have identified some of the extrinsic and intrinsic factors in determining the fiber morphometry of the regenerated nerve. The axon-size and myelination by glial cells were determined through the external axon-glial interactions, whereas the number of axonal microtubules and neurofilaments were intrinsically determined. | en_HK |
dc.language | eng | en_HK |
dc.publisher | IOS Press. The Journal's web site is located at http://www.iospress.nl/html/09226028.php | en_HK |
dc.relation.ispartof | Restorative Neurology and Neuroscience | en_HK |
dc.rights | Restorative Neurology and Neuroscience. Copyright © IOS Press. | en_HK |
dc.subject | Axon-glial interaction | en_HK |
dc.subject | g-ratio | en_HK |
dc.subject | Microtubules | en_HK |
dc.subject | Neurofilaments | en_HK |
dc.subject | Optic nerve | en_HK |
dc.subject | Regenerated optic axons | en_HK |
dc.subject | Schwann cells | en_HK |
dc.title | A morphometric study of optic axons regenerated in a sciatic nerve graft of adult rats | en_HK |
dc.type | Article | en_HK |
dc.identifier.openurl | http://library.hku.hk:4550/resserv?sid=HKU:IR&issn=0922-6028&volume=16&spage=105&epage=116&date=2000&atitle=A+morphometric+study+of+optic+axons+regenerated+in+a+sciatic+nerve+graft+of+adult+rats | en_HK |
dc.identifier.email | So, KF:hrmaskf@hkucc.hku.hk | en_HK |
dc.identifier.email | Tay, D:dkctay@hkucc.hku.hk | en_HK |
dc.identifier.authority | So, KF=rp00329 | en_HK |
dc.identifier.authority | Tay, D=rp00336 | en_HK |
dc.description.nature | link_to_subscribed_fulltext | - |
dc.identifier.pmid | 12671213 | - |
dc.identifier.scopus | eid_2-s2.0-0034060215 | en_HK |
dc.identifier.hkuros | 48572 | en_HK |
dc.identifier.volume | 16 | en_HK |
dc.identifier.issue | 2 | en_HK |
dc.identifier.spage | 105 | en_HK |
dc.identifier.epage | 116 | en_HK |
dc.publisher.place | Netherlands | en_HK |
dc.identifier.scopusauthorid | Wai Kei Chau=7409775360 | en_HK |
dc.identifier.scopusauthorid | So, KF=34668391300 | en_HK |
dc.identifier.scopusauthorid | Tay, D=7006796825 | en_HK |
dc.identifier.scopusauthorid | Dockery, P=7004016702 | en_HK |
dc.identifier.issnl | 0922-6028 | - |