These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: The epileptiform activity induced by 4-aminopyridine in rat amygdala slices: antagonism by non-N-methyl-D-aspartate receptor antagonists.
    Author: Gean PW.
    Journal: Brain Res; 1990 Oct 22; 530(2):251-6. PubMed ID: 1979929.
    Abstract:
    The effects of excitatory amino acid receptor antagonists kynuretic acid and 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) on epileptiform activity induced by 4-aminopyridine (4-AP) were studied in rat amygdala slices using intracellular recording techniques. Five to 10 min after switching to 4-AP-containing solution, spontaneous epileptiform bursts were observed in 35 out of 45 slices studied. The spontaneous epileptiform events consisted of an initial burst followed by a number of afterdischarges. Superfusion with kynuretic acid, a broad-spectrum excitatory amino acid receptor antagonist, reversibly reduced the duration of the spontaneous bursting discharges in a dose-dependent manner. The frequency of spontaneous bursting was also decreased. The IC50, estimated from the graph of the concentration-response relationship, was approximately 130 microM. In addition, CNQX which is a specific non-N-methyl-D-aspartate (NMDA) receptor antagonist blocked the spontaneous and evoked epileptiform bursting. In 11 out of 15 neurons tested, there was a residual depolarizing component remained. This depolarizing component was reversibly blocked by specific NMDA receptor antagonist, D,L-2-amino-5-phosphonovaleate (D,L-APV). Relative to the CNQX-sensitive component, the D,L-APV-sensitive component is much smaller in amplitude and shorter in duration indicating that NMDA receptor plays only a minor role in this process. These data suggest that the generation or propagation of spontaneous epileptiform events induced by 4-AP in the neurons of basolateral amygdala is mediated by excitatory amino acids and that activation of non-NMDA receptors is of primary importance.
    [Abstract] [Full Text] [Related] [New Search]