Sexual differentiation of cortical spreading depression propagation after acute and kindled audiogenic seizures in the Wistar audiogenic rat (WAR)

Epilepsy Res. 2009 Feb;83(2-3):207-14. doi: 10.1016/j.eplepsyres.2008.11.003. Epub 2008 Dec 19.

Abstract

Brain excitability diseases like epilepsy constitute one factor that influences brain electrophysiological features. Cortical spreading depression (CSD) is a phenomenon that can be altered by changes in brain excitability. CSD propagation was presently characterized in adult male and female rats from a normal Wistar strain and from a genetically audiogenic seizure-prone strain, the Wistar audiogenic rat (WAR), both previously submitted (RAS(+)), or not (RAS(-)), to repetitive acoustic stimulation, to provoke audiogenic kindling in the WAR-strain. A gender-specific change in CSD-propagation was found. Compared to seizure-resistant animals, in the RAS(-) condition, male and female WARs, respectively, presented CSD-propagation impairment and facilitation, characterized, respectively, by lower and higher propagation velocities (P<0.05). In contraposition, in the RAS(+) condition, male and female WARs displayed, respectively, higher and lower CSD-propagation rates, as compared to the corresponding controls. In some Wistar and WAR females, we determined estrous cycle status on the day of the CSD-recording as being either estrous or diestrous; no cycle-phase-related differences in CSD-propagation velocities were detected. In contrast to other epilepsy models, such as Status Epilepticus induced by pilocarpine, despite the CSD-velocity reduction, in no case was CSD propagation blocked in WARs. The results suggest a gender-related, estrous cycle-phase-independent modification in the CSD-susceptibility of WAR rats, both in the RAS(+) and RAS(-) situation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acoustic Stimulation / adverse effects
  • Animals
  • Cortical Spreading Depression / physiology*
  • Disease Models, Animal
  • Electroencephalography / methods
  • Female
  • Kindling, Neurologic / physiology*
  • Male
  • Rats
  • Rats, Wistar
  • Seizures / genetics
  • Seizures / physiopathology*
  • Severity of Illness Index
  • Sex Differentiation*