Abstract
Similar to rats, systemic pilocarpine injection causes status epilepticus (SE) and the eventual development of spontaneous seizures and mossy fiber sprouting in C57BL/6 and CD1 mice, but the physiological correlates of these events have not been identified in mice. Population responses in granule cells of the dentate gyrus were examined in transverse slices of the ventral hippocampus from pilocarpine-treated and untreated mice. In Mg2+-free bathing medium containing bicuculline, conditions designed to increase excitability in the slices, electrical stimulation of the hilus resulted in a single population spike in granule cells from control mice and pilocarpine-treated mice that did not experience SE. In SE survivors, similar stimulation resulted in a population spike followed, at a variable latency, by negative DC shifts and repetitive afterdischarges of 3-60 s duration, which were blocked by ionotropic glutamate receptor antagonists. Focal glutamate photostimulation of the granule cell layer at sites distant from the recording pipette resulted in population responses of 1-30 s duration in slices from SE survivors but not other groups. These data support the hypothesis that SE-induced mossy fiber sprouting and synaptic reorganization are relevant characteristics of seizure development in these murine strains, resembling rat models of human temporal lobe epilepsy.
| Original language | English |
|---|---|
| Pages (from-to) | 93-105 |
| Number of pages | 13 |
| Journal | Epilepsy Research |
| Volume | 58 |
| Issue number | 2-3 |
| DOIs | |
| State | Published - Feb 2004 |
Bibliographical note
Funding Information:We thank H. Shibley for technical assistance. Supported by grants from the Louisiana Board of Regents (LEQSF-RD-A-35), the American Heart Association (SDG-0030284N), and the Georges Lurcy Grant Program.
Keywords
- Glutamate photolysis
- Granule cell
- Mossy fiber
- Mouse
- Pilocarpine
- Synaptic reorganization
ASJC Scopus subject areas
- Neurology
- Clinical Neurology