Status Epilepticus Causes Necrotic Damage in the Mediodorsal Nucleus of the Thalamus in Immature Rats
Open Access
- 15 May 2001
- journal article
- Published by Society for Neuroscience in Journal of Neuroscience
- Vol. 21 (10), 3593-3599
- https://doi.org/10.1523/jneurosci.21-10-03593.2001
Abstract
Status epilepticus (StE) in immature rats causes long-term functional impairment. Whether this is associated with structural alterations remains controversial. The present study was designed to test the hypothesis that StE at an early age results in neuronal loss. StE was induced with lithium–pilocarpine in 12-d-old rats, and the presence of neuronal damage was investigated in the brain from 12 hr up to 1 week later using silver and Fluoro-Jade B staining techniques. Analysis of the sections indicated consistent neuronal damage in the central and lateral segments of the mediodorsal nucleus of the thalamus, which was confirmed using adjacent cresyl violet-stained preparations. The mechanism of thalamic damage (necrosis vs apoptosis) was investigated further using TUNEL, immunohistochemistry for caspase-3 and cytochrome c, and electron microscopy. Activated microglia were detected using OX-42 immunohistochemistry. The presence of silver and Fluoro-Jade B-positive degenerating neurons in the mediodorsal thalamic nucleus was associated with the appearance of OX-42-immunopositive activated microglia but not with the expression of markers of programmed cell death, caspase-3, or cytochrome c. Electron microscopy revealed necrosis of the ultrastructure of damaged neurons, providing further evidence that the mechanism of StE-induced damage in the mediodorsal thalamic nucleus at postnatal day 12 is necrosis rather than apoptosis. Finally, these data together with previously described functions of the medial and lateral segments of the mediodorsal thalamic nucleus suggest that some functions, such as adaptation to novelty, might become compromised after StE early in development.Keywords
This publication has 38 references indexed in Scilit:
- Prolonged febrile seizures in the immature rat model enhance hippocampal excitability long termAnnals of Neurology, 2000
- Status Epilepticus Causes Selective Regional Damage and Loss of GABAergic Neurons in the Rat Amygdaloid ComplexEuropean Journal of Neuroscience, 1996
- Sources of presumptive glutamatergic/aspartatergic afferents to the mediodorsal nucleus of the thalamus in the ratJournal of Comparative Neurology, 1992
- Synaptic organization of projections from basal forebrain structures to the mediodorsal thalamic nucleus of the ratJournal of Comparative Neurology, 1991
- Long-Term Effects of Early Status Epilepticus on the Acquisition of Conditioned Avoidance Behavior in RatsEpilepsia, 1986
- Anatomical connections of the nucleus prepositus of the catJournal of Comparative Neurology, 1985
- Thalamocortical connections in newborn miceJournal of Comparative Neurology, 1984
- Axon strata of the cerebral wall in embryonic miceDevelopmental Brain Research, 1984
- A Reliable and Sensitive Method to Localize Terminal Degeneration and Lysosomes in the Central Nervous SystemStain Technology, 1980
- Development of the geniculocortical pathway in ratJournal of Comparative Neurology, 1977