Activation of GABAergic function necessary for afterdischarge generation in rat hippocampal slices.
Involvement of gamma-aminobutyric acid (GABA)-mediated function in epileptogenesis was studied in rat hippocampal slices, in which repetition of high-frequency electrical stimulation induced afterdischarges (ADs) to create an in vitro model for ictal activity. A GABAA receptor antagonist, bicuculline, fully blocked the ADs. On the other hand, the presence of bicuculline caused single stimuli to evoke short-duration epileptiform bursts, a well-known model for interictal activity. Therefore, we conclude that activation of GABAergic function appears to be necessary for ictal activity, while its dysfunction induces interictal activity, and propose a modification to the simple disinhibition hypothesis for epileptogenesis.
Higashima
M
M
Department of Neuropsychiatry, School of Medicine, Kanazawa University, Japan.
Kinoshita
H
H
Yamaguchi
N
N
Koshino
Y
Y
D015761:4-Aminopyridine / Q000494:pharmacology; D000818:Animals; D001640:Bicuculline / Q000494:pharmacology; D004558:Electric Stimulation; D004827:Epilepsy / Q000503:physiopathology*; D006624:Hippocampus / Q000187:drug effects*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D011963:Receptors, GABA-A / Q000187:drug effects*; D013997:Time Factors
D011963:Receptors, GABA-A; D015761:4-Aminopyridine; D001640:Bicuculline