title: GABAB, not GABAA receptors play a role in cortical postictal refractoriness.
abstract: Postictal refractoriness may be taken as an expression of lasting activity of inhibitory systems arresting seizures. We tested drugs interfering with GABAergic inhibitory system in pairs of cortical epileptic afterdischarges induced with 1-min interval in rats. Under control conditions the second stimulation failed to elicit an afterdischarge. This postictal refractoriness was not affected by antagonists of GABAA receptors acting at three binding sites (bicuculline, picrotoxin, benzodiazepine inverse agonist Ro 19-4603) as well as by a less specific antagonist pentetrazol. In contrast, antagonist of GABAB receptors CGP35348 partially blocked the refractoriness. Cooperation of different inhibitory systems is probably necessary to abolish postictal refractoriness in neocortex. This article is part of the Special Issue entitled 'GABAergic Signaling in Health and Disease'.
authors.affiliation: Department of Developmental Epileptology, Institute of Physiology, Academy of Sciences of the Czech Republic, Prague, Czech Republic. Electronic address: maresp@biomed.cas.cz.
authors.forename: Pavel
authors.initials: P
authors.lastname: Mareš
authors.affiliation: Department of Developmental Epileptology, Institute of Physiology, Academy of Sciences of the Czech Republic, Prague, Czech Republic. Electronic address: kubova@biomed.cas.cz.
authors.forename: Hana
authors.initials: H
authors.lastname: Kubová
mesh_terms: D000818:Animals; D001381:Azepines / Q000494:pharmacology; D001640:Bicuculline / Q000494:pharmacology; D002540:Cerebral Cortex / Q000187:drug effects / Q000503:physiopathology; D004558:Electric Stimulation; D004567:Electrodes, Implanted; D004827:Epilepsy / Q000188:drug therapy / Q000503:physiopathology*; D058787:GABA-A Receptor Antagonists / Q000494:pharmacology; D058788:GABA-B Receptor Antagonists / Q000494:pharmacology; D008297:Male; D009943:Organophosphorus Compounds / Q000494:pharmacology; D010433:Pentylenetetrazole / Q000494:pharmacology; D010852:Picrotoxin / Q000494:pharmacology; D017208:Rats, Wistar; D011963:Receptors, GABA-A / Q000378:metabolism*; D018080:Receptors, GABA-B / Q000378:metabolism*
chemical_list: D001381:Azepines; D001640:Bicuculline; D058787:GABA-A Receptor Antagonists; D058788:GABA-B Receptor Antagonists; D009943:Organophosphorus Compounds; D010433:Pentylenetetrazole; D010852:Picrotoxin; D011963:Receptors, GABA-A; D018080:Receptors, GABA-B; C066430:CGP 35348; C056530:Ro 19-4603
keywords: Bicuculline (PubChem CID 102037); CGP35348 (PubChem CID 107699); Cortical seizures; GABA receptors antagonists; Pentylentetrazol (PubChem CID 5917); Picrotoxin (PubChem CID 31304); Postictal refractoriness; Rat; Ro 19-4603 (PubChem CID 127382)