Excitatory amino acids are elevated in human epileptic cerebral cortex.
We used intraoperative electrocorticography to identify and compare specimens from two groups of patients undergoing temporal lobectomy: (1) spiking cortex (12 patients)--epileptic activity recorded over much of the temporal convexity; and (2) nonspiking cortex (9 patients)--temporal convexity free of interictal spiking, epileptic activity confined to the hippocampus and/or amygdala. Comparative amino acid levels were (mumol/g protein, mean +/- SEM): glutamate--spiking 109.8 +/- 1.8, nonspiking 87.4 +/- 2.0 (p less than 0.001); aspartate--spiking 15.2 +/- 0.9, nonspiking 12.2 +/- 0.5 (p less than 0.05); GABA--spiking 15.0 +/- 1.0, nonspiking 13.9 +/- 1.4 (NS); taurine--spiking 14.5 +/- 0.8, nonspiking 12.2 +/- 0.8 (NS); and glycine--spiking 11.5 +/- 0.8, nonspiking 7.4 +/- 0.6 (p less than 0.01). Cortical epileptic activity appears to be associated with elevated concentrations of glutamate, aspartate, and glycine, but not GABA and taurine, perhaps indicating a relative imbalance between putative excitatory and inhibitory amino acid neurotransmitters.
Sherwin
A
A
Department of Neurology and Neurosurgery, Montreal Neurological Institute and Hospital, McGill University, Quebec, Canada.
Robitaille
Y
Y
Quesney
F
F
Olivier
A
A
Villemure
J
J
Leblanc
R
R
Feindel
W
W
Andermann
E
E
Gotman
J
J
Andermann
F
F
D000293:Adolescent; D000328:Adult; D000596:Amino Acids / Q000378:metabolism*; D002540:Cerebral Cortex / Q000378:metabolism*; D004827:Epilepsy / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged
D000596:Amino Acids