title: Anxious and nonanxious mice show similar hippocampal sensory evoked oscillations under urethane anesthesia: difference in the effect of buspirone.
abstract: Hippocampal oscillations recorded under urethane anesthesia are proposed to be modulated by anxiolytics. All classes of clinically effective anxiolytics were reported to decrease the frequency of urethane theta; however, recent findings raise concerns about the direct correlation of anxiolysis and the frequency of hippocampal theta. Here, we took advantage of our two inbred mouse strains displaying extremes of anxiety (anxious (AX) and nonanxious (nAX)) to compare the properties of hippocampal activity and to test the effect of an anxiolytic drugs. No difference was observed in the peak frequency or in the peak power between AX and nAX strains. Buspirone (Bus) applied in 2.5 mg/kg decreased anxiety of AX but did not have any effect on nAX as was tested by elevated plus maze and open field. Interestingly, Bus treatment increased hippocampal oscillatory frequency in the AX but left it unaltered in nAX mice. Saline injection did not have any effect on the oscillation. Paired-pulse facilitation was enhanced by Bus in the nAX, but not in the AX strain. Collectively, these results do not support the hypothesis that hippocampal activity under urethane may serve as a marker for potential anxiolytic drugs. Moreover, we could not confirm the decrease of frequency after anxiolytic treatment.
authors.affiliation: Department of Medical Chemistry, University of Szeged, Dom Square 8, Szeged 6720, Hungary.
authors.forename: János
authors.initials: J
authors.lastname: Horváth
authors.affiliation: Department of Medical Chemistry, University of Szeged, Dom Square 8, Szeged 6720, Hungary.
authors.forename: Balázs
authors.initials: B
authors.lastname: Barkóczi
authors.affiliation: Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Temesvari Körút 32, Szeged 6726, Hungary.
authors.forename: Géza
authors.initials: G
authors.lastname: Müller
authors.affiliation: Biological Research Centre, Hungarian Academy of Sciences, Temesvari Körút 32, Szeged 6726, Hungary.
authors.forename: Viktor
authors.identifier: 0000-0003-4191-379X
authors.initials: V
authors.lastname: Szegedi
mesh_terms: D018686:Anesthetics, Intravenous / Q000494:pharmacology; D000818:Animals; D014151:Anti-Anxiety Agents / Q000494:pharmacology*; D001007:Anxiety / Q000503:physiopathology*; D002065:Buspirone / Q000494:pharmacology*; D004558:Electric Stimulation; D006624:Hippocampus / Q000187:drug effects* / Q000503:physiopathology*; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D010812:Physical Stimulation; D009435:Synaptic Transmission / Q000187:drug effects; D013826:Theta Rhythm / Q000187:drug effects*; D014520:Urethane / Q000494:pharmacology
chemical_list: D018686:Anesthetics, Intravenous; D014151:Anti-Anxiety Agents; D014520:Urethane; D002065:Buspirone