The influence of thalamic GABA transmission on the susceptibility of adult rats to flurothyl induced seizures

D. S. Garant, S. G. Xu, E. F. Sperber, Solomon L. Moshe

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

There is considerable evidence that thalamic nuclei are involved in the propagation and regulation of seizures. In the present study, we investigated the possible role in seizure mechanisms of GABAergic transmission in two thalamic nuclei, the posterior nucleus (PO) and the ventromedial nucleus (VM). Several GABAergic drugs were bilaterally microinfused into PO or VM of adult rats via chronically implanted cannulae, before testing the rats' susceptibility to seizures induced by flurothyl. In PO, infusions of the GABA elevating agent γ-vinyl-GABA (20 μg) or of the GABAA receptor agonist muscimol (100 ng) suppressed both clonic and tonic seizures. Infusions into PO of the GABAA receptor antagonist bicuculline (100 ng) facilitated both these seizure types. Administration of the GABAβ receptor agonist baclofen (200 ng) also suppressed clonic seizure susceptibility. Drug infusions into VM, however, did not significantly modify the susceptibility to seizures. These findings lead us to conclude that GABAergic transmission in the vicinity of the PO, but perhaps not in VM, affects flurothyl seizure susceptibility. We hypothesize that GABA synapses in PO may be part of a seizure propagation or control circuit including striatum, substantia nigra, and superior colliculus.

Original languageEnglish (US)
Pages (from-to)185-192
Number of pages8
JournalEpilepsy Research
Volume15
Issue number3
DOIs
StatePublished - 1993

Fingerprint

Flurothyl
gamma-Aminobutyric Acid
Seizures
Posterior Thalamic Nuclei
GABA Agents
GABA-A Receptor Agonists
GABA Agonists
GABA-A Receptor Antagonists
Thalamic Nuclei
Muscimol
Baclofen
Bicuculline
Superior Colliculi
Substantia Nigra
Pharmaceutical Preparations
Synapses

Keywords

  • Baclofen
  • Bicuculline
  • Convulsion
  • Muscimol
  • Thalamus
  • γ-vinyl-GABA

ASJC Scopus subject areas

  • Clinical Neurology
  • Pediatrics, Perinatology, and Child Health
  • Neurology

Cite this

The influence of thalamic GABA transmission on the susceptibility of adult rats to flurothyl induced seizures. / Garant, D. S.; Xu, S. G.; Sperber, E. F.; Moshe, Solomon L.

In: Epilepsy Research, Vol. 15, No. 3, 1993, p. 185-192.

Research output: Contribution to journalArticle

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