| Project/Area Number |
06455013
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| Research Category |
Grant-in-Aid for General Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Research Field |
広領域
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| Research Institution | Osaka University |
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Principal Investigator |
FUKUDA Yutaka Department of Physiology, Osaka University Medical School, Professor., 医学部, 教授 (90028598)
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| Co-Investigator(Kenkyū-buntansha) |
WATANABE Masami Department of Physiology, Institute for Developmental Research, Aichi Colony, Pr, 主任研究員 (10093486)
INOUE Tetsu Department of Physiology, Osaka University Medical School, Assistant Professor., 医学部, 助手 (60263282)
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| Project Period (FY) |
1994 – 1995
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| Project Status |
Completed (Fiscal Year 1995)
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| Budget Amount *help |
¥8,100,000 (Direct Cost: ¥8,100,000)
Fiscal Year 1995: ¥1,600,000 (Direct Cost: ¥1,600,000)
Fiscal Year 1994: ¥6,500,000 (Direct Cost: ¥6,500,000)
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| Keywords | nerve transplant / optic nerve / retinal ganglion cell / axonal regeneration / visual information transmission / cat / 光情報伝送 |
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| Research Abstract |
Under anesthesia the optic nerve of adult cats was completely sectioned and an autologous sciatic nerve was grafted. Visual functions of the retinal ganglion cells with regenerated axons were studied first by recording single unit activities from regenerated axons and secondly by recording pattern reversed ERGs. Results are summarized below. (1) At about 60 days survival the animals were reanesthetized and immobilized. The grafted nerve was dissected into fine fascicles and single unit activities were recorded with silver wire electrodes. A total of 286 visually responsive units were recorded and they were classified into the following groups based on receptive field properties : 142 were Y cells, 113 were X cells, 19 were W cells and the rest 12 were unclassified. Receptive field center size was normal in most units except for central X cells with enlarged fields. There was a clear asymmetry in the occurrence of ON and Off center cells especially among X cells where there was no OFF center cells while many ON center cells were recorded. (2) After the same surgery of optic nerve section and nerve graft, cats were reanesthetized and ERGs were recorded in response to vertical gratings whose luminance was sinusoidally modulated. From 2 to 8 weeks after the surgery amplitudes of pattern reversed ERGs were gradually reduced but as compared with those of the optic nerve sectioned cats the reduction was mild and more gradual, suggesting some rescuing effects of the nerve graft on axotomized ganglion cells from retrograde cell death.
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