Budget Amount *help |
¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 1991: ¥400,000 (Direct Cost: ¥400,000)
Fiscal Year 1990: ¥400,000 (Direct Cost: ¥400,000)
Fiscal Year 1989: ¥1,300,000 (Direct Cost: ¥1,300,000)
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Research Abstract |
El mice, which are inbred mutant and highly susceptible to convulsive seizures, have been considered a model of complex partial seizures with secondary generalization. In our study, we have observed(1)release of excitatory(aspartate(Asp)and Gglutamate(Glu))and inhibitory(gamma-aminobutyrate(GABA))neurotransmitters from cerebral cortical and hippocampal slices of El mice and(2)effects of Glu antagonists and GABA agonists on the occurrence of El mice convulsions in order to investigate the roles of amino acid neurotransmitters in the convulsive mechanisms of El mice. Our experimental results are as follows. 1. Spontaneous release of Asp increased in the cortical slices. 2. Valproate, which inhibits the El mice convulsions, decreased spontaneous and K@AA+@BB -stimulated Asp release from cortical and hippocampal slices, but it had no effect on Glu or GABA release. 3. Baclofen, which is GABA_B receptor against, inhibit the occurrence of convulsions. 4. Some high affinity GABA_A receptor agonists inhibit the occurrence of convulsions. 5. ZAPA, which is a low affinity GABA_A receptor against, had no effect. 6. Glu receptors have been classified into N-methyl-D-aspartate(NMDA)type, kainate type and quisqualate type receptors. NMDA receptor antagonists and metabotropic NMDA receptor antagonist inhibit the occurrence of convulsions. 7. Kainate or quisqualate receptor antagonists had no effect. 8. These results suggest that GABA_A, NMDA and metabotropic Glu receptor may be involved in the occurrence mechanisms of the El mice convulsions.
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