title: NBQX, a highly selective competitive antagonist of AMPA and KA ionotropic glutamate receptors, increases seizures and mortality following picornavirus infection.
abstract: Seizures occur due to an imbalance between excitation and inhibition, with the balance tipping towards excitation, and glutamate is the predominant excitatory neurotransmitter in the central nervous system of mammals. Since upregulation of expression and/or function of glutamate receptors can contribute to seizures we determined the effects of three antagonists, NBQX, GYKI-52466 and MK 801, of the various ionotropic glutamate receptors, AMPA, NMDA and KA, on acute seizure development in the Theiler's murine encephalomyelitis virus (TMEV)-induced seizure model. We found that only NBQX had an effect on acute seizure development, resulting in a significantly higher number of mice experiencing seizures, an increase in the number of seizures per mouse, a greater cumulative seizure score per mouse and a significantly higher mortality rate among the mice. Although NBQX has previously been shown to be a potent anticonvulsant in animal seizure models, seizures induced by electrical stimulation, drug administration or as a result of genetic predisposition may differ greatly in terms of mechanism of seizure development from our virus-induced seizure model, which could explain the opposite, proconvulsant effect of NBQX observed in the TMEV-induced seizure model.
authors.affiliation: Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT 84112, USA.
authors.forename: Jane E
authors.initials: JE
authors.lastname: Libbey
authors.affiliation: Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT 84112, USA.
authors.forename: Tyler J
authors.initials: TJ
authors.lastname: Hanak
authors.affiliation: Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT 84112, USA.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Doty
authors.affiliation: Department of Pharmacology & Toxicology, University of Utah, 417 Wakara Way, Suite 3211, Salt Lake City, UT 84108, USA.
authors.forename: Karen S
authors.initials: KS
authors.lastname: Wilcox
authors.affiliation: Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT 84112, USA. Electronic address: Robert.Fujinami@hsc.utah.edu.
authors.forename: Robert S
authors.initials: RS
authors.lastname: Fujinami
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D018691:Excitatory Amino Acid Antagonists / Q000633:toxicity*; D006624:Hippocampus / Q000187:drug effects / Q000473:pathology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D010850:Picornaviridae Infections / Q000150:complications*; D037121:Plant Lectins / Q000378:metabolism; D011810:Quinoxalines / Q000633:toxicity*; D012640:Seizures / Q000209:etiology / Q000401:mortality / Q000821:virology
chemical_list: D018691:Excitatory Amino Acid Antagonists; D037121:Plant Lectins; D011810:Quinoxalines; C017707:Ricinus communis agglutinin-1; C062865:2,3-dioxo-6-nitro-7-sulfamoylbenzo(f)quinoxaline
keywords: Antagonists; Excitatory neurotransmitter; Glutamate synapses; Ionotropic glutamate receptors; Picornavirus; Seizures; Theiler's murine encephalomyelitis virus; Viral encephalitis