| Project/Area Number |
17500208
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Neuroscience in general
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| Research Institution | Nagoya University |
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Principal Investigator |
YOSHIMURA Yumiko Nagoya University, Research Institute of Environmental Medicine, Associate Professor, 環境医学研究所, 助教授 (10291907)
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| Project Period (FY) |
2005 – 2006
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| Project Status |
Completed (Fiscal Year 2006)
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| Budget Amount *help |
¥3,700,000 (Direct Cost: ¥3,700,000)
Fiscal Year 2006: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 2005: ¥3,000,000 (Direct Cost: ¥3,000,000)
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| Keywords | visual cortex / silent synapse / critical period / development / dark rearing / NMDA receptor / ラット / ホールセル記録 |
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| Research Abstract |
Visual response properties are refined in an experience-dependent manner during postnatal development in visual cortex. Immature central excitatory synapses often have NMDA receptors but not functional AMPA receptors. Such synapses, called silent synapses, are converted into functional synapses with AMPA receptors. To examine age and experience-dependent changes in silent synapses of visual cortex, we recorded excitatory synaptic currents from layer 2/3 pyramidal neurons in mouse visual cortial slices. Silent synapses are abundantly present in layer 2/3 pyramidal cells before eye opening period and they decreases with development in normal visual environment. This change was prevented by deprivation of visual inputs by rearing mice in dark room from birth and silent synapses remains considerably even until adulthood. This study shows for the first time that silent synapses persist at intracortical synapses in pyramidal cells until adulthood if sensory inputs are deprived from birth. Age and experience dependence of conversion from silent synapses to functional ones is similar to that in modifiability of visual responsiveness of visual cortical cells. It suggests that the transition of silent to functional synapses is one of the synaptic mechanisms underlying experience dependent refinement visual cortical circuit and function.
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