Generalized Non-Convulsive Epilepsy: Focus on GABA-B Receptors

Generalized non convulsive epilepsy (GNCE), also called absence or petit mal epilepsy, is a disease appearing during childhood. EEG, clinical, pharmacological and genetic characteristics differ from those of convulsive or focal epilepsies. No underlying structural or biochemical abnormality has been identified for generalized absence seizures and the etiology of this disorder is unknown. It is unlikely that the precise pathophysiology of GNCE can be resolved in studies that focus on humans. Therefore a number of animal models reproducing the human disease have been developed. The aim of this supplementum is to characterize such models in rodents. First, recent models are extensively described. These include the genetic model of spontaneous GNCE in Strasbourg's Wistar rats and in tottering mice as well as bilateral spike and wave discharges induced by GHB, PTZ or GABA mimetics. Second, this supplementum will also provide very recent information on putative mechanisms underlying generalized absence seizures. Third, various experimental approaches aimed at investigating the neural substrate of this particular kind of epilepsy are described with various electrophysiological, pharmacological, biochemical, metabolic, ionic and molecular data. This supplementum provides an original multidisciplinary approach to the mechanisms involved in GNCE and demonstrates that rodent models are a promising tool which complements the classical feline penicillin model.

Contenu

Human absence epilepsies.- Pharmacological models of generalized absence seizures in rodents.- The tottering mouse: a critical review of its usefulness in the study of the neuronal mechanisms underlying epilepsy.- Genetic absence epilepsy in rats from Strasbourg - A review.- Cortical and thalamic lesions in rats with genetic absence epilepsy.- Role of the thalamic reticular nucleus in the generation of rhythmic thalamo-cortical activities subserving spike and waves.- Responses to N-methyl-D-aspartate are enhanced in rats with Petit-mal-like seizures.- Possible mechanisms underlying hyperexcitability in the epileptic mutant mouse tottering.- The inhibitory control of the substantia nigra over generalized non-convulsive seizures in the rat.- Mapping of cerebral energy metabolism in rats with genetic generalized nonconvulsive epilepsy.- Experimental absence seizures: potential role of gamma-hydroxybutyric acid and GABAB receptors.- GABAB receptor antagonists: potential new anti-absence drugs.- GABA receptors in rats with spontaneous generalized nonconvulsive epilepsy.