Enhanced aspartate release from hippocampal slices of epileptic (El) mice.
The release of putative neurotransmitters [aspartate, glutamate, and gamma-aminobutyric acid (GABA)] was studied in hippocampal slices from adult normal C57BL/6J (B6) and El (epileptic) mice. The El mice, a genetic model of temporal lobe epilepsy, had an average of 86 seizures. Sets of B6 and El hippocampal slices (400 microns thick) were incubated in a series of normal and high potassium (60 mM) buffers in the presence or absence of calcium. The calcium-dependent and calcium-independent potassium-induced release of amino acids was compared in each mouse strain. Release of endogenous amino acids was measured using liquid chromatography with electrochemical detection and was expressed as picomoles of amino acid released per milliliter of incubation buffer per minute of incubation per slice +/- SEM. No significant differences were found between the El and B6 mice for the calcium-dependent potassium-evoked release of glutamate (18.20 +/- 2.62 and 15.41 +/- 3.56), or GABA (17.28 +/- 2.90 and 12.73 +/- 1.37), respectively. Aspartate release, however, was significantly higher in the El mice (6.62 +/- 0.69) than in the B6 mice (3.31 +/- 0.72). These findings suggest that enhanced aspartate release may be related to seizure expression in El mice.
Flavin
H J
HJ
Biology Department, Boston College, Chestnut Hill, Massachusetts 02167.
Wieraszko
A
A
Seyfried
T N
TN
D000818:Animals; D001224:Aspartic Acid / Q000378:metabolism*; D004827:Epilepsy / Q000235:genetics / Q000378:metabolism*; D005971:Glutamates / Q000378:metabolism; D018698:Glutamic Acid; D006624:Hippocampus / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D008818:Mice, Neurologic Mutants; D011188:Potassium / Q000494:pharmacology; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
D005971:Glutamates; D001224:Aspartic Acid; D018698:Glutamic Acid; D005680:gamma-Aminobutyric Acid; D011188:Potassium