Alterations in cytochrome c oxidase activity and energy metabolites in response to kainic acid-induced status epilepticus

Brain Res. 2001 Aug 31;912(1):67-78. doi: 10.1016/s0006-8993(01)02657-9.

Abstract

The effects of kainic acid (KA)-induced limbic seizures have been investigated on cytochrome c oxidase (COx) activity, COx subunit IV mRNA abundance, ATP and phosphocreatine (PCr) levels in amygdala, hippocampus and frontal cortex of rat brain. Rats were killed either 1 h, three days or seven days after the onset of status epilepticus (SE) by CO2 and decapitation for the assay of COx activity and by head-focused microwave for the determination of ATP and PCr. Within 1 h COx activity and COx subunit IV mRNA increased in all brain areas tested between 120% and 130% of control activity, followed by a significant reduction from control, in amygdala and hippocampus on day three and seven, respectively. In amygdala, ATP and PCr levels were reduced to 44% and 49% of control 1 h after seizures. No significant recovery was seen on day three or seven. Pretreatment of rats with the spin trapping agent N-tert-butyl-alpha-phenylnitrone (PBN, 200 mg kg(-1), i.p.) 30 min before KA administration had no effect on SE, but protected COx activity and attenuated changes in energy metabolites. Pretreatment for three days with the endogenous antioxidant vitamin E (Vit-E, 100 mg/kg, i.p.) had an even greater protective effect than PBN. Both pretreatment regimens attenuated KA-induced neurodegenerative changes, as assessed by histology and prevention of the decrease of COx subunit IV mRNA and COx activity in hippocampus and amygdala, otherwise seen following KA-treatment alone. These findings suggest a close relationship between SE-induced neuronal injury and deficits in energy metabolism due to mitochondrial dysfunction.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adenosine Triphosphate / metabolism
  • Amygdala / drug effects
  • Amygdala / enzymology
  • Amygdala / physiopathology
  • Animals
  • Antioxidants / pharmacology
  • Brain / drug effects
  • Brain / enzymology*
  • Brain / physiopathology
  • Cerebral Cortex / drug effects
  • Cerebral Cortex / enzymology
  • Cerebral Cortex / physiopathology
  • Cyclic N-Oxides
  • Electron Transport Complex IV / drug effects
  • Electron Transport Complex IV / genetics
  • Electron Transport Complex IV / metabolism*
  • Energy Metabolism / drug effects
  • Energy Metabolism / physiology*
  • Excitatory Amino Acid Agonists / pharmacology
  • Hippocampus / drug effects
  • Hippocampus / enzymology
  • Hippocampus / physiopathology
  • Kainic Acid / pharmacology
  • Nerve Degeneration / enzymology*
  • Nerve Degeneration / physiopathology
  • Nerve Degeneration / prevention & control
  • Neurotoxins / pharmacology
  • Nitrogen Oxides / pharmacology
  • Oxidative Stress / drug effects
  • Oxidative Stress / physiology*
  • Phosphocreatine / metabolism
  • RNA, Messenger / drug effects
  • RNA, Messenger / metabolism
  • Rats
  • Reactive Oxygen Species / metabolism
  • Status Epilepticus / chemically induced
  • Status Epilepticus / enzymology*
  • Status Epilepticus / physiopathology
  • Vitamin E / pharmacology

Substances

  • Antioxidants
  • Cyclic N-Oxides
  • Excitatory Amino Acid Agonists
  • Neurotoxins
  • Nitrogen Oxides
  • RNA, Messenger
  • Reactive Oxygen Species
  • Phosphocreatine
  • Vitamin E
  • phenyl-N-tert-butylnitrone
  • Adenosine Triphosphate
  • Electron Transport Complex IV
  • Kainic Acid