title: Enhanced non-eupneic breathing following hypoxic, hypercapnic or hypoxic-hypercapnic gas challenges in conscious mice.
abstract: C57BL6 mice display non-eupneic breathing and spontaneous apneas during wakefulness and sleep as well as markedly disordered breathing following cessation of a hypoxic challenge. We examined whether (1) C57BL6 mice display marked non-eupneic breathing following hypercapnic or hypoxic-hypercapnic challenges, and (2) compared the post-hypoxia changes in non-eupneic breathing of C57BL6 mice to those of B6AF1 (57BL6 dam × A/J sire) and Swiss-Webster mice, which display different ventilatory responses than C57BL6 mice. C57BL6 mice displayed marked increases in respiratory frequency and non-eupneic breathing upon return to room-air after hypoxic (10% O2, 90% N2), hypercapnic (5% CO2, 21% O2 and 74% N2) and hypoxic-hypercapnic (10% O2, 5% CO2 and 85% N2) challenges. B6AF1 mice displayed less tachypnea and reduced non-eupneic breathing post-hypoxia, whereas Swiss-Webster mice displayed robust tachypnea with minimal increases in non-eupneic breathing post-hypoxia. These studies demonstrate that non-eupneic breathing increases after physiologically-relevant hypoxic-hypercapnic challenge in C57BL6 mice and suggest that further studies with these and B6AF1 and Swiss-Webster mice will help define the genetics of non-eupneic breathing.
authors.affiliation: Department of Pediatrics, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106-4984, USA.
authors.forename: Paulina M
authors.initials: PM
authors.lastname: Getsy
authors.affiliation: Department of Pediatrics, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106-4984, USA.
authors.forename: Jesse
authors.initials: J
authors.lastname: Davis
authors.affiliation: Department of Pediatrics, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106-4984, USA.
authors.forename: Gregory A
authors.initials: GA
authors.lastname: Coffee
authors.affiliation: Pediatric Respiratory Medicine, University of Virginia School of Medicine, Charlottesville, VA 22908, USA.
authors.forename: Walter J
authors.initials: WJ
authors.lastname: May
authors.affiliation: Pediatric Respiratory Medicine, University of Virginia School of Medicine, Charlottesville, VA 22908, USA.
authors.forename: Lisa A
authors.initials: LA
authors.lastname: Palmer
authors.affiliation: Division of Pulmonary, Critical Care, and Sleep Medicine, University Hospital Case Medical Center and the Louis Stokes Cleveland DVA Medical Center, Case Western Reserve University, Cleveland, OH 44106, USA.
authors.forename: Kingman P
authors.initials: KP
authors.lastname: Strohl
authors.affiliation: Department of Pediatrics, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106-4984, USA. Electronic address: sjl78@case.edu.
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Lewis
mesh_terms: D000818:Animals; D003243:Consciousness; D006935:Hypercapnia / Q000235:genetics / Q000503:physiopathology*; D000860:Hypoxia / Q000150:complications / Q000235:genetics / Q000503:physiopathology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D010993:Plethysmography, Whole Body; D012119:Respiration; D013045:Species Specificity; D059246:Tachypnea / Q000209:etiology / Q000235:genetics / Q000503:physiopathology*
keywords: B6AF1 mice; C57BL6 mice; Hypoxic–hypercapnic gas challenge; Non-eupneic breathing; Swiss-Webster mice