Long-lasting reduction of inhibitory function and gamma-aminobutyric acid type A receptor subunit mRNA expression in a model of temporal lobe epilepsy.

Published

Journal Article

This study evaluated hippocampal inhibitory function and the level of expression of gamma-aminobutyric acid type A (GABAA) receptor mRNA in an in vivo model of epilepsy. Chronic recurrent limbic seizures were induced in rats using injections of pilocarpine. Electrophysiological studies performed on hippocampal slices prepared from control and epileptic animals 1 to 2 months after pilocarpine injections demonstrated a significant hyperexcitability in the epileptic animals. Reduced levels of mRNA expression for the alpha 2 and alpha 5 subunits of the GABAA receptors were evident in the CA1, CA2, and CA3 regions of the hippocampus of epileptic animals. No decrease in mRNA encoding alpha 1, beta 2, or gamma 2 GABAA receptor subunits was observed. In addition, no change in the mRNA levels of alpha CaM kinase II was seen. Selective decreases in mRNA expression did not correlate with neuronal cell loss. The results indicate that selective, long-lasting reduction of GABAA subunit mRNA expression and increased excitability, possibly reflecting loss of GABAergic inhibition, occur in an in vivo model of partial complex epilepsy.

Full Text

Duke Authors

Cited Authors

  • Rice, A; Rafiq, A; Shapiro, SM; Jakoi, ER; Coulter, DA; DeLorenzo, RJ

Published Date

  • September 3, 1996

Published In

Volume / Issue

  • 93 / 18

Start / End Page

  • 9665 - 9669

PubMed ID

  • 8790388

Pubmed Central ID

  • 8790388

International Standard Serial Number (ISSN)

  • 0027-8424

Digital Object Identifier (DOI)

  • 10.1073/pnas.93.18.9665

Language

  • eng

Conference Location

  • United States