Coupling of electrical and metabolic activity during epileptiform discharges.
Changes in electrical activity, ionic microenvironments, and intracellular Ca concentration were measured during recurrent seizures induced by low Mg in slices and slice cultures. In both preparations, initial seizure-like events (SLEs) changed after some time into drug-refractory late recurrent discharges. In slice cultures, there was considerable cell loss in all hippocampal areas after 2 h of status epilepticus. During recurrent SLEs, the NAD(P)H autofluorescence declined, as did intramitochondrial calcium signals, indicating mitochondrial damage. At the same time, ethidium signals indicated increased radical oxygen species production. These alterations could be reduced by alpha-tocopherol, which also protected slice cultures against status epilepticus-induced cell death.
Heinemann
Uwe
U
Johannes Müller Institut für Physiologie, Universitätsklinikum Charité, Humboldt Universität Berlin, Tucholskystrasse 2, D-10117 Berlin, Germany. Uwe.Heinemann@charite.de
Buchheim
K
K
Gabriel
S
S
Kann
O
O
Kovács
R
R
Schuchmann
S
S
D000818:Animals; D004594:Electrophysiology; D018728:Entorhinal Cortex / Q000378:metabolism; D004827:Epilepsy / Q000209:etiology / Q000503:physiopathology*; D005453:Fluorescence; D006624:Hippocampus / Q000503:physiopathology; D008274:Magnesium / Q000378:metabolism; D009249:NADP / Q000378:metabolism; D009924:Organ Culture Techniques; D051381:Rats; D012008:Recurrence
D009249:NADP; D008274:Magnesium