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Effects of anticholinergic bronchodilators on mucociliary transport and airway secretion

T Miyata1, N Matsumoto, H Yuki

  • 1Department of Pharmacological Sciences, Faculty of Pharmaceutical Sciences, Kumamoto University, Japan.

Japanese Journal of Pharmacology
|September 1, 1989
PubMed

Insights

Atropine, ipratropium, and oxitropium were studied for their effects on mucociliary clearance (MCT). While oxitropium and ipratropium did not affect normal MCT, atropine showed inhibitory effects under certain conditions.

Area of Science:

  • Pharmacology
  • Respiratory Physiology

Background:

  • Mucociliary clearance (MCT) is a critical defense mechanism in the airways.
  • Anticholinergic drugs are commonly used for respiratory conditions, but their effects on MCT require clarification.

Purpose of the Study:

  • To investigate the impact of atropine, ipratropium, and oxitropium on mucociliary transport in animal models.
  • To determine if these anticholinergic agents selectively affect endogenous acetylcholine (ACh)-modulated MCT.

Main Methods:

  • Experiments were conducted on pigeons and rabbits to assess MCT.
  • Drugs were administered at varying concentrations (10^-4 to 10^-3 g/ml).
  • Effects on normal MCT and drug-induced accelerations (eserine and ACh) were measured.

Main Results:

  • Atropine, ipratropium, and oxitropium inhibited normal MCT in pigeons.
  • These drugs also inhibited eserine- and ACh-induced MCT acceleration.
  • Only atropine inhibited normal airway secretion in rabbits.
  • Oxitropium and ipratropium did not depress normal MCT in rabbits.

Conclusions:

  • Oxitropium and ipratropium do not appear to depress normal mucociliary clearance.
  • Atropine may inhibit normal MCT under specific circumstances.
  • Anticholinergic drugs might selectively influence MCT regulated by endogenous ACh.

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