title: Respiratory modulation of lingual muscle activity across sleep-wake states in rats.
abstract: In obstructive sleep apnea (OSA) patients, inspiratory activation (IA) of lingual muscles protects the upper airway from collapse. We aimed to determine when rats' lingual muscles exhibit IA. In 5 Sprague-Dawley and 3 Wistar rats, we monitored cortical EEG and lingual, diaphragmatic and nuchal electromyograms (EMGs), and identified segments of records when lingual EMG exhibited IA. Individual segments lasted 2.4-269 s (median: 14.5 s), most (89%) occurred during slow-wave sleep (SWS), and they collectively occupied 0.3-6.1% of the total recording time. IA usually started to increase with a delay after SWS onset and ended with an arousal, or declined prior to rapid eye movement sleep. IA of lingual EMG was not accompanied by increased diaphragmatic activity or respiratory rate changes, but occurred when cortical EEG power was particularly low in a low beta-1 frequency range (12.5-16.4 Hz). A deep SWS-related activation of upper airway muscles may be an endogenous phenomenon designed to protect the upper airway against collapse.
authors.affiliation: Department of Animal Biology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104-6046, USA.
authors.forename: Georg M
authors.initials: GM
authors.lastname: Stettner
authors.forename: Irma
authors.initials: I
authors.lastname: Rukhadze
authors.forename: Graziella L
authors.initials: GL
authors.lastname: Mann
authors.forename: Yanlin
authors.initials: Y
authors.lastname: Lei
authors.forename: Leszek
authors.initials: L
authors.lastname: Kubin
mesh_terms: D000818:Animals; D003627:Data Interpretation, Statistical; D004569:Electroencephalography; D004576:Electromyography; D008297:Male; D018482:Muscle, Skeletal / Q000502:physiology*; D051381:Rats; D015656:Respiratory Mechanics / Q000502:physiology*; D012890:Sleep / Q000502:physiology*; D020181:Sleep Apnea, Obstructive / Q000503:physiopathology; D014059:Tongue / Q000502:physiology*; D014851:Wakefulness / Q000502:physiology*
keywords: EEG power; Genioglossus; Hypoglossal motoneurons; Obstructive sleep apnea; Sleep; Sleep spindles