A.R. and M.A. contributed equally to this work. Current address: Groningen University, Faculty of Medicine, Groningen, The Netherlands.
Memory impairment following status epilepticus in immature rats: time-course and environmental effects
Article first published online: 23 AUG 2002
European Journal of Neuroscience
Volume 16, Issue 3, pages 501–513, August 2002
How to Cite
Rutten, A., Van Albada, M., Silveira, D. C., Cha, B. H., Liu, X., Hu, Y. N., Cilio, M. R. and Holmes, G. L. (2002), Memory impairment following status epilepticus in immature rats: time-course and environmental effects. European Journal of Neuroscience, 16: 501–513. doi: 10.1046/j.1460-9568.2002.02103.x
- Issue published online: 23 AUG 2002
- Article first published online: 23 AUG 2002
- Received 12 January 2002, revised 29 May 2002, accepted 30 May 2002
- water maze;
Status epilepticus (SE) has a high mortality and morbidity rate in children. Disturbances in learning and memory are frequently associated with SE although it is not clear when the cognitive deficits occur. If cognitive dysfunction occurs immediately following the seizure, the window of opportunity for therapeutic intervention is limited. The first goal of this study was to determine the timing of cognitive dysfunction following SE in weanling rats. As there is evidence that enriching the environment can improve cognitive and motor deficits following brain injury, our second goal was to determine whether environmental enrichment improves cognitive function following SE. Rats underwent lithium-pilocarpine-induced SE at postnatal (P) day 20 and were then tested for visual-spatial memory in the water maze at P22, P25, P30, or P50. Rats with SE performed significantly worse in the water maze than control rats at all time points. Once the time-courses of visual-spatial memory deficits were determined, a second group of P20 rats were subjected to SE and were then placed in an enriched environment (enriched group) or remained in standard cages in the vivarium (nonenriched group) for 28 days. Following environmental manipulation, the animals were tested in the water maze. Rats housed in an enriched environment following the SE performed substantially better in the water maze than rats housed in standard cages. However, no differences were found between the enriched and nonenriched groups in EEG or histological evaluation. Although SE results in cognitive impairment within days of the seizure, housing in an enriched environment after SE has a beneficial effect on cognitive performance in rats.