Axonal regeneration of retinal ganglion cells studied by a model of an extensive crush lesion of the optic nerve.

• Other Authors: Kong, Wai-Chi.
• Format: Others
• Language: English; Chinese
• Published: 2005
• Subjects: Nervous system > Regeneration; Optic nerve > Diseases; Retinal ganglion cells; Nerve Regeneration; Optic Nerve Diseases; Retinal Ganglion Cells
• Online Access: http://library.cuhk.edu.hk/record=b6074170; http://repository.lib.cuhk.edu.hk/en/item/cuhk-343799

Despite that the RGC axons closely associated with astrocytes, the role of astrocytes in RGC regeneration was uncertain. In view of this, the effect of cultured adult astrocytes on RGC regeneration through an extensive ON lesion segment was studied. Adult ON astrocytes were prepared by sub-culturing of cells migrating out of ON explants. A small hole in the ON was punctured by 27G needle and about 0.5 to 1.0mul (1000 cells) cultured astrocytes was injected into the extensive ON lesion segment. We found that cultured adult astrocytes promoted significant RGC axon regeneration in the extensive ON lesion. === Finally, co-transplantation of intravitreal PN followed by transplantation of astrocytes into the extensive lesion has a synergistic effect on the regrowth of RGC axons, as indicated by the maximum distance achieved by regenerating axons and integrated intensity of staining of the CTB-labeled axons. Transplanatation of VPN+AST, VPN+NAST and NPN+AST as 3.9, 2.5 and l.9 times more potent in inducing regeneration than that of NPN+NAST as shown by integrated intensity measurement. However, co-transplantation of PN and astrocytes could not enhance RGC survival. (Abstract shortened by UMI.) === In this study, we have established an extensive lesion paradigm to study the behavior of injured retinal ganglion cell (RGC) axons after ON crush in adult golden hamster. We found that RGC axons regenerated in the extensive lesion for 406.8mum at 1 week post-crush to 1174.0mum at 4 weeks post-crush. RGC axons were able to regenerate the entire lesion segment but they terminated precisely at the interface between the lesion and the distal segment of the ON. Regrowing axons were intimately associated with astrocytes which repopulated the lesion segment. Repopulated oligodendrocytes were scattered in the lesion segment and myelin debris was significantly decreased in the lesion segment with time. === It is commonly believed that central nervous system (CNS) neurons are unable to regenerate after injury. Recently, there have been several lines of evidence showing that damaged CNS neurons can undergo axonal regeneration under appropriate conditions. Since the retina and optic nerve (ON) are regarded as part of the CNS, therefore, they are used as a model to study CNS regeneration. === Kong Wai Chi. === "July 2005." === Adviser: Y.P. Cho. === Source: Dissertation Abstracts International, Volume: 67-07, Section: B, page: 3616. === Thesis (Ph.D.)--Chinese University of Hong Kong, 2005. === Includes bibliographical references (p. 96-115). === Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. === Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. === Abstracts in English and Chinese. === School code: 1307.