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A Reversible, Non-invasive Method for Airway Resistance Measurements and Bronchoalveolar Lavage Fluid Sampling in Mice
Published on: April 13, 2010
Midazolam reverses histamine-induced bronchoconstriction in dogs
K Hirota1, N Ohtomo, Y Hashimoto
1Department of Anesthesiology, University of Hirosaki School of Medicine, Japan.
Canadian Journal of Anaesthesia = Journal Canadien D'Anesthesie
|November 14, 1997
Summary
Midazolam demonstrates a spasmolytic effect on constricted airways, promoting bronchodilation. This effect was not reversed by flumazenil, indicating a distinct mechanism of action for midazolam in airway relaxation.
Area of Science:
- Anesthesiology
- Pharmacology
- Respiratory Medicine
Background:
- Midazolam is a common sedative and anesthetic induction agent.
- Its potential bronchodilating effects remain incompletely understood.
- This study investigates midazolam's impact on airway smooth muscle.
Purpose of the Study:
- To evaluate the relaxant effects of midazolam on the airway.
- To determine if midazolam possesses bronchodilating properties.
- To assess the role of flumazenil in antagonizing midazolam's airway effects.
Main Methods:
- Mongrel dogs were anesthetized and paralyzed.
- Bronchoconstriction was induced using histamine.
- Airway cross-sectional area was measured using fiberoptic bronchoscopy.
- Midazolam and flumazenil were administered intravenously to assess their effects.
Main Results:
- Histamine significantly reduced bronchial cross-sectional area.
- Midazolam, at doses above 0.1 mg/kg, dose-dependently increased bronchial cross-sectional area, indicating bronchodilation.
- Flumazenil did not reverse the bronchodilating effect of midazolam.
- Midazolam reduced histamine-induced adrenaline release, an effect reversed by flumazenil.
Conclusions:
- Midazolam exhibits a spasmolytic effect on constricted airways.
- The bronchodilating effect of midazolam is not antagonized by flumazenil.
- Midazolam may offer therapeutic benefits in managing airway constriction.
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