Abstract | PURPOSE: Pathophysiologic mechanisms underlying temporal lobe epilepsy (TLE) are still poorly understood. One major hypothesis links alterations in energy metabolism to glutamate excitotoxicity associated with seizures in TLE. The purpose of this study was to determine whether changes in the activities of enzymes critical in energy and neurotransmitter metabolism contributed to the alterations in metabolic status leading to the excitotoxic effects of glutamate. METHODS: RESULTS: We found that GDH activity was significantly decreased in the temporal cortex mainly in the MTLE group. A similar trend was recognized in the hippocampus of the MTLE. In all three patient groups, GDH activity was considerably lower, and AAT and LDH activities were higher in cortex of MTLE as compared with the corresponding activities in hippocampus (p<0.05). In the MTLE cortex and hippocampus, GDH activities were negatively correlated with the duration since the first intractable seizure. CONCLUSIONS: Our results support the hypothesis suggesting major alteration in GDH activity mainly in the MTLE group. It is proposed that significant alterations in the enzyme activities may be contributing to decreased metabolism of glutamate, leading to its accumulation.
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Authors | Gauri H Malthankar-Phatak, Nihal de Lanerolle, Tore Eid, Dennis D Spencer, Kevin L Behar, Susan S Spencer, Jung H Kim, James C K Lai |
Journal | Epilepsia
(Epilepsia)
Vol. 47
Issue 8
Pg. 1292-9
(Aug 2006)
ISSN: 0013-9580 [Print] United States |
PMID | 16922873
(Publication Type: Comparative Study, Journal Article, Research Support, N.I.H., Extramural)
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Chemical References |
- Glutamic Acid
- L-Lactate Dehydrogenase
- Glutamate Dehydrogenase
- Aspartate Aminotransferases
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Topics |
- Adolescent
- Adult
- Aspartate Aminotransferases
(metabolism)
- Child
- Diagnosis, Differential
- Energy Metabolism
- Epilepsy, Temporal Lobe
(diagnosis, enzymology, physiopathology)
- Female
- Glutamate Dehydrogenase
(metabolism)
- Glutamic Acid
(metabolism, physiology)
- Hippocampus
(enzymology, metabolism)
- Humans
- L-Lactate Dehydrogenase
(metabolism)
- Male
- Middle Aged
- Neocortex
(enzymology, metabolism)
- Temporal Lobe
(enzymology, metabolism)
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