Neocortical and hippocampal changes after multiple pilocarpine-induced status epilepticus in rats

Alexandre Valotta Da Silva, Maria Cristina Regondi, Barbara Cipelletti, Carolina Frassoni, Esper Abrão Cavalheiro, Roberto Spreafico

Research output: Contribution to journalArticle

Abstract

Purpose: Multiple episodes of pilocarpine-induced status epilepticus (SE) in developing rats (P7-P9) lead to progressive epileptiform activity and severe cognitive impairment in adulthood. The present work studied possible underlying abnormalities in the neocortex and hippocampus of pilocarpine-treated animals. Methods: Wistar rats were submitted to pilocarpine-induced SE at P7, P8, and P9, and were killed at P35. Immunocytochemistry was performed on 50-μm vibratome sections, by using antibodies against nonphosphorylated neurofilament (SMI-311), parvalbumin (PV), calbindin (CB), calretinin (CR), and glutamate decarboxylase (GAD-65). Ten-micron cryostat sections were processed for immunohistoblot by using antibodies against GluR1, GluR2/3, and GluR4 α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor subunits and NR2ab N-methyl-D-aspartate (NMDA) receptor subunit. Results: Adult rats submitted to SE at P7-9 showed: (a) altered distribution of neocortical interneurons; (b) increased cortical and reduced hippocampal GAD-65 expression; and (c) altered expression of hippocampal AMPA and NMDA receptors. Conclusions: We conclude that multiple SE episodes during P7-9 generate long-lasting disturbances that underlie behavioral and electrographic abnormalities later in life.

Original languageEnglish
Pages (from-to)636-642
Number of pages7
JournalEpilepsia
Volume46
Issue number5
DOIs
Publication statusPublished - May 2005

    Fingerprint

Keywords

  • Early insult
  • Immature brain
  • Immunocytochemistry
  • Immunohistoblot

ASJC Scopus subject areas

  • Clinical Neurology
  • Neuroscience(all)

Cite this