Mechanisms for gravity stress-induced synaptic plasticity in rat hippocampus
Project/Area Number |
16591853
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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 |
Functional basic dentistry
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Research Institution | Tokyo Medical and Dental University |
Principal Investigator |
KUMEI Yasuhiro Tokyo Medical and Dental University, Hard Tissue Engineering, Lecturer, 大学院医歯学総合研究科, 講師 (30161714)
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Co-Investigator(Kenkyū-buntansha) |
TODA Kazuo Nagasaki University, Developmental and Reconstructive Medicine, Professor, 大学院医歯薬学総合研究科, 教授 (80134708)
SHIMOKAWA Hitoyata Tokyo Medical and Dental University, Hard Tissue Engineering, Associate Professor, 大学院医歯学総合研究科, 助教授 (80014257)
SHIMOKAWA Reiko Tokyo Medical and Dental University, Neuropathology, Assistant Professor, 難治疾患研究所, 助手 (90014349)
OKADA Yukio Nagasaki University, Developmental and Reconstructive Medicine, Associate Professor, 大学院医歯薬学総合研究科, 助教授 (60136687)
ZEREDO Jorge Nagasaki University, Developmental and Reconstructive Medicine, Associate Professor, 大学院医歯薬学総合研究科, 助手 (10363459)
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Project Period (FY) |
2004 – 2005
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Project Status |
Completed (Fiscal Year 2005)
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Budget Amount *help |
¥3,200,000 (Direct Cost: ¥3,200,000)
Fiscal Year 2005: ¥1,600,000 (Direct Cost: ¥1,600,000)
Fiscal Year 2004: ¥1,600,000 (Direct Cost: ¥1,600,000)
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Keywords | hippocampus / gravity / synaptic plasticity / LTP / telemetry / パッチクランプ / 脳スライス |
Research Abstract |
We measured the field potential in the CA1 region as responding to electrical stimulation of Schaffer's collaterals. The relative ratio of amplitude of the negative deflection, as compared between 100 vs. 1Hz stimulation, was 40% increased in the 2G-slices. Hypergravity enhanced unit activities and synaptic transmission in the CA1 region, which may underlie the gravity-response mechanism of rat. The relative ratio of amplitude was 1.3 at 1G (basal level), and increased to 1.8 at 2G hypergravity. The efficiency of synaptic transmission in the hippocampal CA1 region was increased by 2G-exposure. The hypergravity-induced early-phase LTP (long-term potentiation) might reflect the increase of firing frequency in the CA1 region. Similar data were reported by Ishii et al. in that early-phase LTP was induced in mice that were exposed to 4G for 48 hrs with enhancement of AMPA receptor phosphorylation. Another group reported the site and time-dependent modulation of acute behavioral stress on hippocampal LTP induction. Data suggest molecular mechanism for the hippocampal LTP, glutamate-receptor, Ca ^<2+>, serotonin (5-HT) enforcement of LTP, and GABA inhibitory neurons on hippocampal plasticity, which will finally result in disordered learning and memory of gravitational informations. Hippocampus, amygdala, and hypothalamus are interconnected structures by neuronal circuit. The modulation of neuronal activity in these areas might play causative roles in the mechanism underlying the response to gravitational alteration.
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Report
(3 results)
Research Products
(4 results)