Late expression of FosB transcription factor in 4-aminopyridine-induced seizures in the rat cerebral cortex.
In this study, the immunolocalization of FosB transcription factor was investigated in acute and chronic experimental models of seizures induced by 4-aminopyridine. Wistar rats were injected intraperitoneally daily with 5mg/kg 4-aminopyridine for 1, 4, 8 and 12 days and sacrificed 24h after the last injection. Corresponding control groups received the solvent of 4-aminopyridine. Immunohistochemistry revealed an increase in FosB immunolabelling in the frontal cortex in 4-aminopyridine-treated animals compared to controls, both in acute and chronic time course groups. The dentate gyrus displayed elevated FosB immunopositivity only after repeatedly applied convulsant (4-aminopyridine), i.e. following 4, 8 and 12 days of treatment, but no significant immunolocalization was observed in the hippocampus proper. The neuronal localization of FosB after 12 days of 4-aminopyridine-induced convulsions was analysed by means of FosB-parvalbumin double immunolabelling. The increased number of double-labelled cells was significant in the frontal cortex, hilum of the dentate fascia and region CA1 of the hippocampus. We conclude that the studied neocortical and allocortical areas showed a different pattern of FosB immunolocalization, which suggests a relative deficiency of transcriptional regulation in the Ammon's horn and may be responsible for distinct response to seizure-induced cellular insult.
Bagosi
Andrea
A
Department of Anatomy, Faculty of Medicine, University of Szeged, P.O. Box 427, H-6701 Szeged, Hungary. bagosi@anatomy.szote.u-szeged.hu
Bakos
Mónika
M
Krisztin-Péva
Beáta
B
Mihály
András
A
D015761:4-Aminopyridine / Q000494:pharmacology*; D000818:Animals; D002467:Cell Nucleus / Q000378:metabolism; D002540:Cerebral Cortex / Q000187:drug effects* / Q000378:metabolism*; D005786:Gene Expression Regulation; D006624:Hippocampus / Q000378:metabolism; D007150:Immunohistochemistry; D009474:Neurons / Q000378:metabolism; D010320:Parvalbumins / Q000096:biosynthesis; D026902:Potassium Channel Blockers / Q000494:pharmacology; D016760:Proto-Oncogene Proteins c-fos / Q000096:biosynthesis*; D051381:Rats; D012640:Seizures; D013997:Time Factors; D014157:Transcription Factors / Q000378:metabolism
C483820:Fosb protein, rat; D010320:Parvalbumins; D026902:Potassium Channel Blockers; D016760:Proto-Oncogene Proteins c-fos; D014157:Transcription Factors; D015761:4-Aminopyridine