title: NMDA preconditioning attenuates cortical and hippocampal seizures induced by intracerebroventricular quinolinic acid infusion.
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.
authors.affiliation: Departamento de Bioquímica, CCB, Universidade Federal de Santa Catarina, Trindade, Florianópolis, SC, 88040-900, Brazil. samuelvandresen@yahoo.com.br
authors.forename: Samuel
authors.initials: S
authors.lastname: Vandresen-Filho
authors.forename: Alexandre A
authors.initials: AA
authors.lastname: Hoeller
authors.forename: Bruno A
authors.initials: BA
authors.lastname: Herculano
authors.forename: Marcelo
authors.initials: M
authors.lastname: Duzzioni
authors.forename: Filipe S
authors.initials: FS
authors.lastname: Duarte
authors.forename: Tetsadê C B
authors.initials: TC
authors.lastname: Piermartiri
authors.forename: Carina C
authors.initials: CC
authors.lastname: Boeck
authors.forename: Thereza C M
authors.initials: TC
authors.lastname: de Lima
authors.forename: José
authors.initials: J
authors.lastname: Marino-Neto
authors.forename: Carla I
authors.initials: CI
authors.lastname: Tasca
mesh_terms: D000818:Animals; D058256:Brain Waves / Q000187:drug effects / Q000502:physiology; D002540:Cerebral Cortex / Q000187:drug effects* / Q000503:physiopathology; D006624:Hippocampus / Q000187:drug effects* / Q000503:physiopathology; D057967:Infusions, Intraventricular; D008297:Male; D051379:Mice; D016202:N-Methylaspartate / Q000494:pharmacology* / Q000627:therapeutic use; D018696:Neuroprotective Agents / Q000494:pharmacology; D017378:Quinolinic Acid / Q000008:administration & dosage* / Q000037:antagonists & inhibitors* / Q000633:toxicity; D012640:Seizures / Q000139:chemically induced / Q000188:drug therapy*
chemical_list: D018696:Neuroprotective Agents; D016202:N-Methylaspartate; D017378:Quinolinic Acid