title: Airway surface liquid composition in mice.
abstract: Airway surface liquid (ASL) lines the conducting airways of the respiratory tract. We collected small samples of this liquid from the lower tracheae of anesthetized C57BL/6 mice and determined its ionic composition (in mM: 87.2 Na(+), 4.7 K(+), and 57.0 Cl(-)). Intravenous methacholine produced significant increases in the concentrations of Na(+), K(+), and Cl(-) within ASL. A limited analysis of liquid from cystic fibrosis transmembrane conductance regulator (CFTR) knockout mice revealed no significant differences compared with littermate controls; however, Pseudomonas aeruginosa infection led to an increase in the salt concentration of ASL in cftr(+/+) mice. Morphometric measurements of tracheal submucosal gland volume revealed significant differences between inbred mouse strains, corresponding to ease of ASL collection. We conclude that although submucosal glands may be responsible for the production of some ASL, the ionic composition of this liquid is actively regulated by the underlying epithelial cells.
authors.affiliation: Meakins-Christie Laboratories, Montreal Chest Institute Research Centre, McGill University Health Centre, Quebec, Canada.
authors.forename: E A
authors.initials: EA
authors.lastname: Cowley
authors.forename: K
authors.initials: K
authors.lastname: Govindaraju
authors.forename: C
authors.initials: C
authors.lastname: Guilbault
authors.forename: D
authors.initials: D
authors.lastname: Radzioch
authors.forename: D H
authors.initials: DH
authors.lastname: Eidelman
mesh_terms: D000818:Animals; D001826:Body Fluids / Q000737:chemistry*; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000235:genetics; D004573:Electrolytes / Q000032:analysis; D005088:Exocrine Glands / Q000033:anatomy & histology; D005838:Genotype; D007477:Ions; D008297:Male; D016210:Methacholine Chloride / Q000494:pharmacology; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout / Q000235:genetics; D009994:Osmolar Concentration; D011552:Pseudomonas Infections / Q000378:metabolism; D013045:Species Specificity; D013048:Specimen Handling / Q000379:methods; D014132:Trachea / Q000033:anatomy & histology / Q000378:metabolism*
chemical_list: D004573:Electrolytes; D007477:Ions; D016210:Methacholine Chloride; D019005:Cystic Fibrosis Transmembrane Conductance Regulator