The purpose of this research is to understand the properties of mucus in persons with COPD, specifically Chronic Bronchitis. We hypothesize that those with Chronic Bronchitis have dehydrated mucus, and thus have a harder time coughing it out of their lungs. This leads to a greater vulnerability for lung infection, inflammation and airflow obstruction. Ultimately, our goal is to understand how mucus dehydration contributes to the progression of COPD/Chronic Bronchitis so that better therapies and interventions can be developed for future generations.

Specific Aim I directly tests the hypothesis that mucus clearance is impaired due to mucus dehydration. It measures 1) COPD Mucociliary and Cough Clearance 2) mucus hydration 3) the concentrations of the dominant regulators of airway hydration and 4) the consequences of mucus dehydration on mucus biophysical properties and bacterial infection.

Specific Aim II tests the hypothesis that COPD acute exacerbations are associated with failures of mucus clearance. Measurements will be similar to that of Specific Aim I, but conducted during periods of baseline health, acute exacerbation and recovery.

Specific Aim III tests whether airway surface hydration with 7% Hypertonic Saline will restore clearance in the basal state and during a COPD acute exacerbation. COPD subjects will be exposed to inhaled Hypertonic Saline during periods of baseline health and acute exacerbation. Acute efficacy via measures of mucus clearance and spirometry will studied.

Inclusion Criteria:

• history of COPD/chronic bronchitis defined as having a productive cough for three months of the year for at least two successive years
• greater than or equal to a 10 pack year cigarette smoking history
• ability to perform spirometry

Exclusion Criteria:

• unstable lung disease
• allergy to study medications
• radiation exposure within past year exceeding Federal Regulation Limits

Community members with a history of cigarette smoking and COPD/chronic bronchitis.