2001 Fiscal Year Final Research Report Summary
Investigation of mechanism of central nervous system disorder due to chlorinated hydrocarbons
| Project/Area Number |
11470097
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Hygiene
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| Research Institution | Yamaguchi University |
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Principal Investigator |
OKUDA Masayuki Yamaguchi University, School of Medicine, Associate Professor, 医学部, 助教授 (50274171)
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| Co-Investigator(Kenkyū-buntansha) |
KUNITSUGU Ichiro Yamaguchi University, School of Medicine, Research Associate, 医学部, 助手 (80314798)
SHINODA Akira Yamaguchi University, School of Medicine, Professor, 医学部, 教授 (40192108)
HOBARA Tatsuya Yamaguchi University, School of Medicine, Professor, 医学部, 教授 (10116501)
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| Project Period (FY) |
1999 – 2001
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| Keywords | neuron / patch clump / Fluo-3 / calcium ion / organic solvents / chlorinatedhydrocarbons / trichloroethylene / bromopropane |
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| Research Abstract |
Calcium ion in neurons plays an important role in development of action potential, release of neurotransmitter and intracellular signaling with synapse formation and physiological functions. Intracellular calcium ion is derivedfrom either influx from the extracellular fluid through the membranecalcium channelso release out of the intracellular calcium store sites. Organic solvents used in the field of manufacturing and service industry cause clinical symptoms related to depression of central nervous system function.
We have dissociated dorsal root ganglion neurons from neonatal rat to measure the voltage-dependent calcium current in a whole cell mode of the patch clump. Trichloroethane and trichloroethyene decreased the calcium current. And intervals of the action potential in the current clump mode were shortened. We also found the involvement of other voltage-gated cation channels. Next we investigated the change of intracellular calcium ion concentration released from the intracellular calcium stores with a fluo-indicator Fluo-3. We used in this experiments caffeine which modifies ryanodine receptor of intracellular calcium store , and ATP which stimulates the nucleotide receptor of the DRG neurons. Caffeine induced the increasing of the intracellular calcium level, and trichloroethyleneinhibited the increasing. The rise of the intracellular calcium level was also impaired with 1-bromopropane and 2-bromopropane. These studies suggested that some of organic solvents could act on both the plasma membrane of the neurons and cytoplasmic organelles in entering though the plasma membraneand finally modify the action potential and neurotransmitterrelease.
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