title: The Relationship of Mucus Concentration (Hydration) to Mucus Osmotic Pressure and Transport in Chronic Bronchitis.
abstract: BACKGROUND
  Chronic bronchitis (CB) is characterized by persistent cough and sputum production. Studies were performed to test whether mucus hyperconcentration and increased partial osmotic pressure, in part caused by abnormal purine nucleotide regulation of ion transport, contribute to the pathogenesis of CB.
  
  
  OBJECTIVE
  We tested the hypothesis that CB is characterized by mucus hyperconcentration, increased mucus partial osmotic pressures, and reduced mucus clearance.
  
  
  METHODS
  We measured in subjects with CB as compared with normal and asymptomatic smoking control subjects indices of mucus concentration (hydration; i.e., percentage solids) and sputum adenine nucleotide/nucleoside concentrations. In addition, sputum partial osmotic pressures and mucus transport rates were measured in subjects with CB.
  
  
  RESULTS
  CB secretions were hyperconcentrated as indexed by an increase in percentage solids and total mucins, in part reflecting decreased extracellular nucleotide/nucleoside concentrations. CB mucus generated concentration-dependent increases in partial osmotic pressures into ranges predicted to reduce mucus transport. Mucociliary clearance (MCC) in subjects with CB was negatively correlated with mucus concentration (percentage solids). As a test of relationships between mucus concentration and disease, mucus concentrations and MCC were compared with FEV1, and both were significantly correlated.
  
  
  CONCLUSIONS
  Abnormal regulation of airway surface hydration may slow MCC in CB and contribute to disease pathogenesis.
authors.affiliation: 1 Pulmonary and Critical Care Medicine, Department of Medicine.
authors.forename: Wayne H
authors.initials: WH
authors.lastname: Anderson
authors.affiliation: 1 Pulmonary and Critical Care Medicine, Department of Medicine.
authors.forename: Raymond D
authors.initials: RD
authors.lastname: Coakley
authors.affiliation: 2 Marsico Lung Institute/Cystic Fibrosis Research Center.
authors.forename: Brian
authors.initials: B
authors.lastname: Button
authors.affiliation: 1 Pulmonary and Critical Care Medicine, Department of Medicine.
authors.forename: Ashley G
authors.initials: AG
authors.lastname: Henderson
authors.affiliation: 3 Marsico Lung Institute/Center for Environmental Medicine, Asthma, and Lung Biology.
authors.forename: Kirby L
authors.initials: KL
authors.lastname: Zeman
authors.affiliation: 3 Marsico Lung Institute/Center for Environmental Medicine, Asthma, and Lung Biology.
authors.forename: Neil E
authors.initials: NE
authors.lastname: Alexis
authors.affiliation: 3 Marsico Lung Institute/Center for Environmental Medicine, Asthma, and Lung Biology.
authors.forename: David B
authors.initials: DB
authors.lastname: Peden
authors.affiliation: 2 Marsico Lung Institute/Cystic Fibrosis Research Center.
authors.forename: Eduardo R
authors.initials: ER
authors.lastname: Lazarowski
authors.affiliation: 2 Marsico Lung Institute/Cystic Fibrosis Research Center.
authors.forename: C William
authors.initials: CW
authors.lastname: Davis
authors.affiliation: 2 Marsico Lung Institute/Cystic Fibrosis Research Center.
authors.forename: Summer
authors.initials: S
authors.lastname: Bailey
authors.affiliation: 1 Pulmonary and Critical Care Medicine, Department of Medicine.
authors.forename: Fred
authors.initials: F
authors.lastname: Fuller
authors.affiliation: 1 Pulmonary and Critical Care Medicine, Department of Medicine.
authors.forename: Martha
authors.initials: M
authors.lastname: Almond
authors.affiliation: 4 Department of Statistics, and.
authors.forename: Bahjat
authors.initials: B
authors.lastname: Qaqish
authors.affiliation: 4 Department of Statistics, and.
authors.forename: Elena
authors.initials: E
authors.lastname: Bordonali
authors.affiliation: 5 Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
authors.forename: Michael
authors.initials: M
authors.lastname: Rubinstein
authors.affiliation: 1 Pulmonary and Critical Care Medicine, Department of Medicine.|3 Marsico Lung Institute/Center for Environmental Medicine, Asthma, and Lung Biology.
authors.forename: William D
authors.initials: WD
authors.lastname: Bennett
authors.affiliation: 2 Marsico Lung Institute/Cystic Fibrosis Research Center.
authors.forename: Mehmet
authors.initials: M
authors.lastname: Kesimer
authors.affiliation: 1 Pulmonary and Critical Care Medicine, Department of Medicine.|2 Marsico Lung Institute/Cystic Fibrosis Research Center.
authors.forename: Richard C
authors.initials: RC
authors.lastname: Boucher
mesh_terms: D000328:Adult; D000368:Aged; D029481:Bronchitis, Chronic / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009079:Mucociliary Clearance / Q000502:physiology*; D009093:Mucus / Q000737:chemistry* / Q000502:physiology*; D009997:Osmotic Pressure / Q000502:physiology*
keywords: COPD; mucociliary clearance; mucus hyperconcentration