title: Xenon-induced inhibition of synchronized bursts in a rat cortical neuronal network.
abstract: Xenon (Xe) and other inert gases produce anesthesia via an inhibitory mechanism in neuronal networks. To better understand this mechanism, we measured the electrical signals from cultured rat cortical neuronal networks in a multi-electrode array (MEA) under an applied Xe pressure. We used the MEA to measure the firing of the neuronal network with and without Xe gas pressurized to 0.3MPa. The MEA system monitored neuronal spikes on 16 electrodes (each 50×50μm(2)) at a sampling rate of 20kHz. The embryo rat cortical cells were first cultured on MEAs without Xe for approximately 3weeks, at which time they produced synchronized bursts that indicate maturity. Then, with an applied Xe pressure, the synchronized bursts quickly ceased, whereas single spikes continued. The Xe-induced inhibition-recovery of neuronal network firing was reversible: after purging Xe from the system, the synchronized bursts gradually resumed. Thus, Xe did not inhibit single neuron firing, yet reversibly inhibited the synaptic transmission. This finding agrees with the channel-blocker and a modified-hydrate hypothesis of anesthesia, but not the lipid-solubility hypothesis.
authors.affiliation: Division of Applied Physics, Faculty of Engineering, Hokkaido University, N13 W8 Kita-ku, Sapporo, Japan. t-uchida@eng.hokudai.ac.jp
authors.forename: T
authors.initials: T
authors.lastname: Uchida
authors.forename: S
authors.initials: S
authors.lastname: Suzuki
authors.forename: Y
authors.initials: Y
authors.lastname: Hirano
authors.forename: D
authors.initials: D
authors.lastname: Ito
authors.forename: M
authors.initials: M
authors.lastname: Nagayama
authors.forename: K
authors.initials: K
authors.lastname: Gohara
mesh_terms: D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D018685:Anesthetics, Inhalation / Q000494:pharmacology*; D000818:Animals; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000187:drug effects* / Q000502:physiology; D009415:Nerve Net / Q000187:drug effects* / Q000502:physiology; D009433:Neural Inhibition / Q000187:drug effects* / Q000502:physiology; D009474:Neurons / Q000187:drug effects* / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D014978:Xenon / Q000494:pharmacology*
chemical_list: D018685:Anesthetics, Inhalation; D014978:Xenon