title: GABAergic Synchronization in Epilepsy.
abstract: γ-Aminobutyric acid (GABA) is the main inhibitory neurotransmitter in the cerebral cortex. GABAergic inhibition enables synchronization of activity in cortical networks, and contributes to generation of variety of brain activity patterns. In relation to epilepsy, GABAergic inhibition has been traditionally viewed as the main mechanism counterbalancing glutamatergic excitation and preventing hypersynchronous neuronal discharges. Indeed, deficits in GABAergic functions most commonly result in a hyperexcitable epileptic state, and many of the currently used antiepileptic drugs act through enhancement of GABAergic functions. However, a number of observations show that some epileptiform activity patterns involve synchronization by GABAergic mechanisms. These include two main categories that will be reviewed here: (1) synchronization of epileptiform oscillations based on GABAergic inhibition, and (2) epileptiform events driven by depolarizing and excitatory GABA. The conclusion is reached that GABAergic control of spike timing, either through inhibition or excitation under certain conditions, may work as a powerful synchronizing mechanism during epilepsy.
authors.affiliation: INMED-INSERM U901, 13273 Marseille Cedex 09, France Aix-Marseille University, 13273 Marseille Cedex 09, France Laboratory of Neurobiology, Kazan Federal University, 420008 Kazan, Russia.
authors.forename: Roustem
authors.initials: R
authors.lastname: Khazipov
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000818:Animals; D000927:Anticonvulsants / Q000494:pharmacology; D003344:Cortical Synchronization / Q000502:physiology; D004195:Disease Models, Animal; D004827:Epilepsy / Q000209:etiology* / Q000503:physiopathology; D006801:Humans; D009415:Nerve Net / Q000502:physiology; D010634:Phenobarbital / Q000494:pharmacology; D051381:Rats; D018079:Receptors, GABA / Q000502:physiology; D009435:Synaptic Transmission / Q000502:physiology; D005680:gamma-Aminobutyric Acid / Q000502:physiology*
chemical_list: D000927:Anticonvulsants; D018079:Receptors, GABA; D005680:gamma-Aminobutyric Acid; D010634:Phenobarbital