Influence of inhaled atropine on lung mucociliary function in humans.
The influence of aerosolized atropine sulfate on lung airway mucus clearance was investigated in healthy human subjects who were nonsmokers. Mucus transport was measured with radiolabeled insoluble particles inhaled by mouth and deposited onto mucosal surfaces; subsequent retention of radiolabel was quantitated over a 4- to 5-h period by a noninvasive, posteriorly aligned, gamma camera. Placebo and atropine clearance tests were matched in a given subject for initial and for final (24-h postinhalation) deposition pattern of labeled aerosol at the onset and conclusion, respectively, of tracheobronchial particle clearance. In seven subjects mucociliary function was delayed after inhalation of 0.025 mg/kg body weight atropine sulfate as compared with placebo (0.9% NaCl). On the basis of the area under the activity versus time curves, retention times during atropine exceeded placebo times by more than 30% (p less than 0.01). At 90 min postatropine inhalation, the Vmax50 exceeded baseline values by 21% (p less than 0.01). Urine retention was present in one subject and xerostomia was present in all subjects after atropine. These data suggest that a single dose of atropine sulfate delivered topically to the airway surfaces delays the continuous flow of airway mucus in healthy subjects and that basal autonomic tone is an inherent factor for optimal secretion and/or removal of tracheobronchial secretions.
Groth
M L
ML
Pulmonary Disease Division, VAMC, Northport, New York.
Langenback
E G
EG
Foster
W M
WM
D000280:Administration, Inhalation; D000328:Adult; D000336:Aerosols; D001285:Atropine / Q000008:administration & dosage*; D005260:Female; D005541:Forced Expiratory Volume / Q000187:drug effects / Q000502:physiology; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000502:physiology; D008297:Male; D009079:Mucociliary Clearance / Q000187:drug effects* / Q000502:physiology; D011877:Radionuclide Imaging; D012016:Reference Values; D013671:Technetium Tc 99m Sulfur Colloid; D013997:Time Factors; D014797:Vital Capacity / Q000187:drug effects / Q000502:physiology; D014980:Xenon Radioisotopes
D000336:Aerosols; D014980:Xenon Radioisotopes; D013671:Technetium Tc 99m Sulfur Colloid; D001285:Atropine