Abstract
Extracellular field recordings were performed in guinea-pig and rat neocortical slice preparations maintained in vitro. Bath application of the convulsant drug 4-aminopyridine (4-AP, 100 μM) induced spontaneous epileptiform potentials in 80% of the guinea-pig neocortical slices and only in 6% of the neocortical slices from rat. In both species spontaneous epileptiform activity consisted of a 4-16 s long ictal-like discharge that recurred with a frequency range of 0.01-0.02 Hz. In rat neocortical slices stimulus-induced responses resembled the spontaneous occurring epileptiform events. Ictal-like discharges in guinea-pig neocortical slices were blocked by the N-methyl-d-aspartate (NMDA) receptor antagonist 3-((±-2-carboxypiperazine-4-yl)propyl-1-phosphonic acid (5 μM), while those in the rat desappeared during perfusion with the non-NMDA excitatory amino acid receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (1-3 μM). These results indicate that the neocortex of guinea-pig has a higher propensity to generate 4-AP-induced spontaneous epileptiform activity than that of rat. Furthermore the epileptiform activity in these two species requires a different involvement of excitatory amino acid receptors.
Original language | English |
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Pages (from-to) | 157-160 |
Number of pages | 4 |
Journal | Neuroscience Letters |
Volume | 154 |
Issue number | 1-2 |
DOIs | |
Publication status | Published - May 14 1993 |
Keywords
- 4-Aminopyridine
- Epileptiform activity
- Guinea-pig
- Neocortex
- Rat
ASJC Scopus subject areas
- Neuroscience(all)