title: Breathing and brain state: urethane anesthesia as a model for natural sleep.
abstract: Respiratory control differs dramatically across sleep stages. Indeed, along with rapid eye movements (REM), respiration was one of the first physiological variables shown to be modulated across sleep stages. The study of sleep stages, their physiological correlates, and neurobiological underpinnings present a challenge because of the fragility and unpredictability of individual stages, not to mention sleep itself. Although anesthesia has often substituted as a model for a unitary stage of slow-wave (non-REM) sleep, it is only recently that urethane anesthesia has been proposed to model the full spectrum of sleep given the presence of spontaneous brain state alternations and concurrent physiological correlates that appear remarkably similar to natural sleep. We describe this model, its parallels with natural sleep, and its power for studying modulation of respiration. Specifically, we report data on the EEG characteristics across brain states under urethane anesthesia, the dependence of brain alternations on neurotransmitter systems, and the observations on state dependent modulation of respiration.
authors.affiliation: Department of Physiology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada; WCHRI, Women and Children's Health Research Institute, University of Alberta, Edmonton, AB, Canada; Centre for Neuroscience, University of Alberta, Edmonton, AB, Canada. Electronic address: silviap@ualberta.ca.
authors.forename: Silvia
authors.initials: S
authors.lastname: Pagliardini
authors.forename: Gregory D
authors.initials: GD
authors.lastname: Funk
authors.forename: Clayton T
authors.initials: CT
authors.lastname: Dickson
mesh_terms: D000758:Anesthesia; D018686:Anesthetics, Intravenous; D000818:Animals; D001921:Brain / Q000187:drug effects / Q000502:physiology*; D004569:Electroencephalography / Q000187:drug effects; D006801:Humans; D008954:Models, Biological; D012119:Respiration / Q000187:drug effects*; D015656:Respiratory Mechanics / Q000187:drug effects / Q000502:physiology; D012890:Sleep / Q000502:physiology*; D014520:Urethane
chemical_list: D018686:Anesthetics, Intravenous; D014520:Urethane
keywords: Anesthesia; REM sleep; Respiratory control; Sleep cycle; Slow-wave sleep; State alternation