NMDA preconditioning attenuates cortical and hippocampal seizures induced by intracerebroventricular quinolinic acid infusion

Neurotox Res. 2013 Jul;24(1):55-62. doi: 10.1007/s12640-012-9359-y. Epub 2012 Nov 27.

Abstract

Searching for new therapeutic strategies through modulation of glutamatergic transmission using effective neuroprotective agents is essential. Glutamatergic excitotoxicity is a common factor to neurodegenerative diseases and acute events such as cerebral ischemia, traumatic brain injury, and epilepsy. This study aimed to evaluate behavioral and electroencephalographic (EEG) responses of mice cerebral cortex and hippocampus to subconvulsant and convulsant application of NMDA and quinolinic acid (QA), respectively. Moreover, it aimed to evaluate if EEG responses may be related to the neuroprotective effects of NMDA. Mice were preconditioned with NMDA (75 mg/kg, i.p.) and EEG recordings were performed for 30 min. One day later, QA was injected (36.8 nmol/site) and EEG recordings were performed during 10 min. EEG analysis demonstrated NMDA preconditioning promotes spike-wave discharges (SWDs), but it does not display behavioral manifestation of seizures. Animals that were protected by NMDA preconditioning against QA-induced behavioral seizures, presented higher number of SWD after NMDA administration, in comparison to animals preconditioned with NMDA that did display behavioral seizures after QA infusion. No differences were observed in latency for the first seizure or duration of seizures. EEG recordings after QA infusion demonstrated there were no differences in the number of SWD, latency for the first seizure or duration of seizures in animals pretreated with saline or in animals preconditioned by NMDA that received QA. A negative correlation was identified between the number of NMDA-induced SWD and QA-induced seizures severity. These results suggest a higher activation during NMDA preconditioning diminishes mice probability to display behavioral seizures after QA infusion.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Brain Waves / drug effects
  • Brain Waves / physiology
  • Cerebral Cortex / drug effects*
  • Cerebral Cortex / physiopathology
  • Hippocampus / drug effects*
  • Hippocampus / physiopathology
  • Infusions, Intraventricular
  • Male
  • Mice
  • N-Methylaspartate / pharmacology*
  • N-Methylaspartate / therapeutic use
  • Neuroprotective Agents / pharmacology
  • Quinolinic Acid / administration & dosage*
  • Quinolinic Acid / antagonists & inhibitors*
  • Quinolinic Acid / toxicity
  • Seizures / chemically induced
  • Seizures / drug therapy*

Substances

  • Neuroprotective Agents
  • N-Methylaspartate
  • Quinolinic Acid