Metabolic and pathological effects of temporal lobe epilepsy in rat brain detected by proton spectroscopy and imaging

Brain Res. 1997 Jan 2;744(1):57-67. doi: 10.1016/s0006-8993(96)01071-2.

Abstract

The goal of these experiments was to test the hypothesis that in an animal model of temporal lobe epilepsy (TLE), magnetic resonance spectroscopic measurement of N-acetylaspartate (NAA) and other metabolites, together with magnetic resonance imaging, provides a sensitive in vivo method to localize and monitor the progression of neuronal cell death and gliosis. Seizures were induced in rats by unilateral hippocampal injection of kainate. Magnetic resonance measurements were made from 1 to 84 days using proton spectroscopic imaging (1H-MRSI), T2-weighted imaging (T2WI) and diffusion-weighted imaging (DWI). The results were compared with findings on histological sections. Decreased NAA and creatine levels and increased apparent diffusion coefficient of water were found in the ipsilateral hippocampus after 14 days where neuronal loss and gliosis were observed. In the contralateral hippocampus a significant increase of choline level was observed. These results suggest that 1H-MRSI is a useful in vivo method for localizing neuronal loss and may also indicate additional pathological and metabolic alterations. In addition, DWI may be a useful method for in vivo detection of tissue alterations due to TLE.

Publication types

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

MeSH terms

  • Animals
  • Aspartic Acid / analogs & derivatives
  • Aspartic Acid / analysis
  • Behavior, Animal / physiology
  • Choline / analysis
  • Creatine / analysis
  • Epilepsy, Temporal Lobe / chemically induced
  • Epilepsy, Temporal Lobe / diagnosis*
  • Epilepsy, Temporal Lobe / metabolism*
  • Excitatory Amino Acid Agonists
  • Kainic Acid
  • Magnetic Resonance Imaging
  • Magnetic Resonance Spectroscopy
  • Male
  • Rats
  • Rats, Sprague-Dawley
  • Temporal Lobe / chemistry
  • Temporal Lobe / drug effects
  • Temporal Lobe / physiopathology
  • Time Factors

Substances

  • Excitatory Amino Acid Agonists
  • Aspartic Acid
  • N-acetylaspartate
  • Creatine
  • Choline
  • Kainic Acid