The involvement of Na+, K+-ATPase activity and free radical generation in the susceptibility to pentylenetetrazol-induced seizures after experimental traumatic brain injury

J Neurol Sci. 2011 Sep 15;308(1-2):35-40. doi: 10.1016/j.jns.2011.06.030. Epub 2011 Jul 6.

Abstract

Although the importance of brain trauma as risk factor for the development of epilepsy is well established, the mechanisms of epileptogenesis are not well understood. In the present study, we revealed that the injection of a subthreshold dose of PTZ (30 mg/Kg, i.p.) after 5 weeks of injury induced by Fluid Percussion Brain Injury (FPI) decreased latency for first clonic seizures, increased the time of spent generalized tonic-clonic seizures and electrocorticographic (EEG) wave amplitude. In addition, statistical analysis revealed that N-acetylcysteine (NAC) (100mg/kg) supplementation during 5 weeks after neuronal injury protected against behavioral and electrographical seizure activity elicited by subthreshold dose of PTZ. The supplementation of this antioxidant compound also protected against the Na(+),K(+)-ATPase activity inhibition and concomitant increase in the levels of oxidative stress markers (protein carbonylation and thiobarbituric acid-reactive substances-TBARS) in site and peri-contusional cortical tissue. In summary, the current experiments clearly showed that FPI model induces early posttraumatic seizures and suggest that an alteration in the lipid/protein oxidation, membrane fluidity, and Na(+),K(+)-ATPase activity may be correlated with neuronal excitability, a significant component of the secondary injury cascade that accompanies TBI.

Publication types

  • Comparative Study

MeSH terms

  • Animals
  • Brain Injuries / complications
  • Brain Injuries / enzymology
  • Brain Injuries / metabolism*
  • Enzyme Activation / drug effects
  • Enzyme Activation / physiology
  • Free Radicals / metabolism*
  • Male
  • Pentylenetetrazole / toxicity*
  • Rats
  • Rats, Wistar
  • Reaction Time / drug effects
  • Reaction Time / physiology
  • Seizures / chemically induced*
  • Seizures / enzymology
  • Seizures / metabolism*
  • Sodium-Potassium-Exchanging ATPase / metabolism*
  • Sodium-Potassium-Exchanging ATPase / physiology
  • Thiobarbituric Acid Reactive Substances / metabolism

Substances

  • Free Radicals
  • Thiobarbituric Acid Reactive Substances
  • Sodium-Potassium-Exchanging ATPase
  • Pentylenetetrazole