Related Experiment Video
Updated: Jun 6, 2026

Assessment of Respiratory Function in Conscious Mice by Double-chamber Plethysmography
Published on: July 10, 2018
Maximal degree of airway narrowing induced by methacholine and adenosine monophosphate: relationship with the
Luis Prieto1, Victoria Lopez, Carmen Perez-Frances
1Universidad de Valencia, Valencia, Spain. prieto_jes@gva.es
Bronchoconstrictor-induced changes in forced vital capacity (FVC) do not reliably indicate airway plateau levels in asthma or allergic rhinitis patients. Pro-inflammatory stimuli can alter FVC and plateau independently, suggesting FVC changes are not a surrogate for plateau estimation.
Area of Science:
- Pulmonary Medicine
- Respiratory Physiology
- Allergy and Immunology
Background:
- Forced vital capacity (FVC) changes may indirectly detect airway plateau in response to bronchoconstrictors.
- Understanding this relationship is crucial for interpreting airway responsiveness tests.
Purpose of the Study:
- To investigate the correlation between plateau levels induced by methacholine or adenosine monophosphate (AMP) and the resulting FVC decrease.
- To assess how allergen exposure affects this relationship in sensitive individuals.
Main Methods:
- Airway responsiveness to high-dose methacholine and AMP was assessed in asthma and allergic rhinitis patients.
- Concentration-response curves were analyzed using the slope of FVC vs. forced expiratory volume in 1 second (FEV1) and plateau levels.
- Allergen-induced changes were studied in pollen-sensitive patients.
Main Results:
- The slope of FVC vs. FEV1 was comparable between patients with and without a plateau.
- In pollen-allergic patients, the plateau level with methacholine increased significantly during the pollen season (16.8% to 21.7%), while FVC vs. FEV1 slope changes were not significant.
- Similar trends were observed with AMP.
Conclusions:
- Methacholine or AMP-induced FVC changes are not significantly related to the presence or level of airway plateau in asthma and allergic rhinitis.
- Pro-inflammatory stimuli can independently alter FVC and plateau, decoupling these measures.
- Bronchoconstrictor-induced FVC changes should not be used as a surrogate for plateau level estimation.
Related Concept Videos
Chronic Obstructive Pulmonary Disease III: Chronic Bronchitis Features
Chronic Obstructive Pulmonary Disease-II: Pathophysiology
Chronic Inflammation
Direct-Acting Cholinergic Agonists: Therapeutic Uses
Factors Affecting Pulmonary Ventilation
Alveolar Surface Tension
The alveolar fluid lines the luminal surface of the alveoli and exerts a force called surface tension. This force is caused by the polar water molecules in the liquid being more strongly attracted to each...
Antiasthma Drugs: Methylxanthines
Theophylline is thought to inhibit phosphodiesterase enzymes, increasing intracellular levels of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP). This rise in cAMP and cGMP concentrations stimulates cardiac function,...
Adrenergic Agonists: Mixed-Action Agents
Ephedrine and pseudoephedrine lack a catecholamine group, making them less susceptible to degradation by metabolic enzymes. They have increased oral bioavailability and lipophilicity, resulting in a longer duration of action. Their response is reduced by...
