1998 Fiscal Year Final Research Report Summary
Analysis of synaptic formation on the cerebral pyramidal cell associated with the projection of thalamocortical axons
Project/Area Number |
09680736
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Nerve anatomy/Neuropathology
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Research Institution | The institute of Physical and Chemical Research (RIKEN) (1998) Yamagata University (1997) |
Principal Investigator |
ISHII Katsuyoushi RIKEN, Laboratory for Neural Architecture, Research Scientist, 神経構築技術開発チーム, 研究員 (40202931)
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Project Period (FY) |
1997 – 1998
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Keywords | cerebral cortex / pyramidal cell / GABAergic neuron / thalamocortical axon / intracellular injection / Lucifer yellow / developmental / rat |
Research Abstract |
I examined the outgrowth of thalamocortical axons in the developing rat and their distribution in the cerebral cortex with DiI and Biocytin labeling methods. These findings showed the morphology of thalamocortical axons as they arrive at the intermediate zone at embryonic day(ED) 16, as they enter into the deep layer of the cerebral cortex at ED18, and begin to make terminal branching in developing layer IV at postnatal day(PD)2 and form more clearly periodic and dense clusters by PD7. To obtain well-labeled GABAergic neurons in layer IV of the cerebral cortex for morphological analysis, I injected dye into GABA-immunopositive neurons in fixed slices. I injected Biocytin from a posterior direction into the right thalpmus of rats and labeled thalamocortical axons with Biocytin anterogradely. Sections were reacted for GABA immunohistochemistry and revealed GABA positive neurons with FITC. So I injected Lucifer yellow intracellularly into FITC labeled cells in layer IV of the cerebral cortex. Injected cells were imaged with a laser conforcal microscope. Most injected neurons were multipolar at all ages. At PD7 or younger injected cells with vertically elongated or polygonal soma and a major dendrite vertically elongated were more common. At PD14 and 21, many injected- cells had spherical or oval soma and showed more dendrites radiated from the soma in all directions. These findings show the morphology of GABAergic neurons change into mature type between PD7 and PD 14. To study the synaptic formation on the cerebral pyramidal cell associated with the projection of thalamocortical axons, I labeled thalamocortical axons with Biocytin anterogradely and cerebral pyramidal cells with Fluoro-Gold retrogradely. So I injected Lucifer yellow intracellularly into Fluoro-Gold labeled cells in layers V and II/III of the cerebral cortex. Using specimens for an electron microscope, the study of synaptic formation on the cerebral pyramidal cell is in progress.
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Research Products
(14 results)