title: Reactive oxidant species in piriform cortex extracellular fluid during seizures induced by systemic kainic acid in rats.
abstract: Kainic acid (KA) administered systemically to rats produces seizures and brain damage. We measured an increase in reactive oxidant species (ROS) during KA-induced seizures in the extracellular fluid (ECF) of the piriform cortex, a brain region known to be subsequently damaged. Intracerebral microdialysis samples were collected and assayed for isoluminol-dependent chemiluminescence before and after injection of KA (16 mg/kg, i.p.). Hydrogen peroxide (H2O2) concentrations were calculated from catalase-sensitive chemiluminescence, the difference between total and catalase-resistant chemiluminescence. During generalized tonic-clonic seizures, both total and catalase-resistant chemiluminescence increased significantly in samples from brain ECF. Catalase-resistant chemiluminescence, most likely produced by ascorbic acid, increased for a full hour during sustained seizure activity. H2O2 concentrations showed a trend towards elevation during seizures. Increased ROS suggest that oxidative stress occurs in brain ECF during sustained seizure activity.
authors.affiliation: Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, USA.
authors.forename: M E
authors.initials: ME
authors.lastname: Layton
authors.forename: T L
authors.initials: TL
authors.lastname: Pazdernik
mesh_terms: D000818:Animals; D001205:Ascorbic Acid / Q000378:metabolism; D002540:Cerebral Cortex / Q000187:drug effects / Q000378:metabolism*; D005110:Extracellular Space / Q000187:drug effects / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000378:metabolism; D007608:Kainic Acid / Q000494:pharmacology*; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000378:metabolism*; D012640:Seizures / Q000139:chemically induced* / Q000378:metabolism
chemical_list: D017382:Reactive Oxygen Species; D006861:Hydrogen Peroxide; D001205:Ascorbic Acid; D007608:Kainic Acid