Opposite changes in GABAA receptor function in the CA1-3 area and fascia dentata of kindled rat hippocampus

J Neurochem. 1995 Jun;64(6):2615-21. doi: 10.1046/j.1471-4159.1995.64062615.x.


Muscimol-stimulated radiotracer 36CI- uptake in synaptoneurosomes was used to investigate the function of the GABAA receptor complex in the CA1-3 area and fascia dentata (granular and molecular layers and hilus) of rats kindled by stimulation, twice a day, of the Schaffer collateral fibers. Two kindled groups were studied: (a) 24 h after the last generalized tonic-clonic seizure [fully kindled (FK) stage] and (b) 28 days after the last generalized seizure (long-term stage). Synaptoneurosomes were prepared in parallel from subslices of the CA1-3 area and fascia dentata. In FK animals, the muscimol-stimulated 36CI- uptake was significantly reduced by 21% in the CA1-3 area in comparison with nonstimulated controls, whereas a significant increase of 29% was found in the fascia dentata. Significant changes were no longer present at 4 weeks after the last generalized seizure. The observed changes in muscimol-stimulated 36CI- uptake at the FK stage closely parallel the recently observed changes in [3H]muscimol binding in the CA1 area and fascia dentata. These results indicate that kindling causes a transiently decreased GABAA receptor-mediated function in the CA1-3, in contrast to an increased GABAA receptor-mediated function in the fascia dentata.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Chlorides / pharmacokinetics
  • Hippocampus / metabolism*
  • Hippocampus / ultrastructure
  • Kindling, Neurologic*
  • Male
  • Microscopy, Electron
  • Muscimol / pharmacology
  • Osmolar Concentration
  • Rats
  • Rats, Wistar
  • Receptors, GABA / metabolism*
  • Seizures / metabolism
  • Synaptosomes / metabolism
  • Time Factors
  • Tissue Distribution


  • Chlorides
  • Receptors, GABA
  • Muscimol