X-ray microanalysis of airway surface liquid in the mouse

• Published in: American journal of physiology. Lung cellular and molecular physiology 2005-05, Vol.288 (5), p.L874-L878
• Main Authors: Kozlova, Inna, Nilsson, Harriet, Phillipson, Mia, Riederer, Brigitte, Seidler, Ursula, Colledge, William H, Roomans, Godfried M
• Format: Article
• Language: English
• Subjects: Animals; Cystic Fibrosis - metabolism; Dextrans; Electron Probe Microanalysis; Extravascular Lung Water - metabolism; Female; Freezing; Male; Mice; Mice, Inbred CFTR; Mice, Inbred Strains; Microspheres; Respiratory Mucosa - metabolism; Respiratory Mucosa - ultrastructure; Respiratory Mucosa/metabolism/ultrastructure; Trachea - metabolism; Trachea - ultrastructure; Trachea/metabolism/ultrastructure
• ISSN: 1040-0605; 1522-1504; 1522-1504
• DOI: 10.1152/ajplung.00303.2004

1 Department of Medical Cell Biology, University of Uppsala, Uppsala, Sweden; 2 Department of Gastroenterology, Hepatology, and Endocrinology, Hannover Medical School, Hannover, Germany; and 3 Physiology Department, University of Cambridge, Cambridge, United Kingdom Submitted 10 August 2004 ; accepted in final form 22 December 2004 The ionic composition of airway surface liquid (ASL) has been debated, and, in particular for the mouse, a wide range of values has been published. Two techniques were developed to measure the elemental composition of the ASL. X-ray microanalysis of ASL was carried out at low temperature on trachea removed from isoflurane-anesthetized animals and shock-frozen. In the second technique, dextran beads were placed on top of the epithelium of the trachea removed from pentobarbital-anesthetized animals, left to equilibrate with the ASL, dried, and subjected to X-ray microanalysis. Both techniques showed that mouse tracheal ASL has significantly lower concentrations of Na and Cl ( 60–80 mM) than serum. Differences between the two techniques were due to different sampling of mucus. CFTR(–/–) mice had significantly higher concentrations of Na and Cl in their ASL than age-matched controls. Pilocarpine or isoproterenol stimulation significantly reduced the ion concentrations in tracheal ASL. ASL was also collected with the dextran bead method from the nasal cavity in situ in pentobarbital-anesthetized animals. In control animals, the elemental composition of nasal fluid was similar to that of tracheal ASL. Pilocarpine stimulation caused a significant increase in Na, Cl, and K; stimulation with isoproterenol or phenylephrine caused a significant increase only in K. It is concluded that mouse ASL under unstimulated conditions is hypotonic, which may be related to the relative paucity of submucosal glands in the mouse trachea. cystic fibrosis; ion transport Address for reprint requests and other correspondence: G. M. Roomans, Dept. of Medical Cell Biology, Univ. of Uppsala, Box 571, SE-75123 Uppsala, Sweden (E-mail: godfried.roomans{at}medcellbiol.uu.se )