title: Transmitter release in hippocampal slices from rats with limbic seizures produced by systemic administration of kainic acid.
abstract: The systemic injection of kainic acid (KA) has been shown to destroy neurons in the hippocampus and to induce limbic-type seizure activity. However, little is known on the neurochemical events that are associated with this convulsant effect. In the present work we studied the spontaneous and the K(+)-stimulated release of labeled tau-aminobutyric acid (GABA), glutamate, serotonin and dopamine, in hippocampal slices of KA-treated rats, at the moment of clinical seizures (2 h) and 72 h later. At the onset of convulsions we found a 40-45% decrease in the K(+)-stimulated release of GABA. The release of the other neurotransmitters was not significantly affected by KA treatment. After 72 h GABA release was still reduced by 30-40%. It is concluded that the epileptogenic effect of KA in the hippocampus is probably related to a diminished inhibitory GABAergic neurotransmission.
authors.affiliation: Laboratorio de Neuroquímica, Instituto Nacional de Neurología y Neurocirugía, Secretaría de Salud, México D.F., México.
authors.forename: C
authors.initials: C
authors.lastname: Arias
authors.forename: T
authors.initials: T
authors.lastname: Montiel
authors.forename: R
authors.initials: R
authors.lastname: Tapia
mesh_terms: D000818:Animals; D004298:Dopamine / Q000378:metabolism; D005971:Glutamates / Q000378:metabolism; D018698:Glutamic Acid; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism*; D007608:Kainic Acid; D007700:Kinetics; D008032:Limbic System / Q000503:physiopathology*; D008297:Male; D011188:Potassium / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D012640:Seizures / Q000139:chemically induced / Q000503:physiopathology*; D012701:Serotonin / Q000378:metabolism; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
chemical_list: D005971:Glutamates; D012701:Serotonin; D018698:Glutamic Acid; D005680:gamma-Aminobutyric Acid; D011188:Potassium; D007608:Kainic Acid; D004298:Dopamine