Related Experiment Video
Updated: May 8, 2026
A Reversible, Non-invasive Method for Airway Resistance Measurements and Bronchoalveolar Lavage Fluid Sampling in Mice
Published on: April 14, 2010
Elevated circulating adenosine level potentiates antigen-induced immediate bronchospasm and bronchoconstrictor
1Department of Pathophysiology, National Korányi Institute for TB and Pulmonology, Budapest, Hungary.
Background:
Adenosine causes bronchoconstriction in asthmatic patients, and it is also accepted that adenosine influences histamine release from activated human mast cells and basophils in vitro.
Objective:
In this study we tested the hypothesis that adenosine potentiates both the airway narrowing and the release of bronchoconstrictor mediators induced by ovalbumin challenge in sensitized guinea pigs.
Methods:
After ovalbumin sensitization, 4 groups were studied: control group, adenosine group (ADO), ovalbumin group (OA), and adenosine plus ovalbumin group (ADO + OA). Changes in airway resistance were assessed from continuously recorded pulmonary insuffilation pressure (PIP). The concentration of histamine, PGD2, and thromboxane B2 were determined from bronchoalveolar lavage fluids.
Results:
Adenosine alone (6 mg/kg intravenously) did not influence baseline values of PIP and the mediator concentrations; however, ovalbumin (10 mg/kg intravenously) increased both the PIP and the levels of the measured mediators compared with the control and ADO groups. When ovalbumin challenge was preceded by adenosine administration, both PIP and mediator levels were significantly enhanced compared with values obtained after simple ovalbumin provocation (ADO + OA vs OA: P <.05).
Conclusion:
These results suggest that adenosine potentiates the airway narrowing induced by ovalbumin challenge and that this effect may develop through facilitation of the release of bronchoconstrictor mediators during the immediate airway response.
Related Concept Videos
02:06Allergic Reactions
01:26Adrenergic Receptors: β Subtype
Isoprenaline > Adrenaline > Noradrenaline
Neurotransmitter binding to these receptors causes activation of adenylyl cyclase resulting in increased concentrations of cAMP and modulation of calcium ion channels within the cell. They are further classified into β1, β2, and β3 subtypes.
β1-adrenoceptors: β1-adrenoceptors have equal affinities for...
01:30Adrenergic Agonists: Direct-Acting Agents
These agents can be classified...
01:28Adrenergic 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...
01:30Adrenergic Agonists: Therapeutic Uses
Emergency and Intensive Care Unit (ICU) applications: Pressor agents increase blood pressure, heart rate, and contractility in shock and organ failure situations. Dopamine can induce vasodilation and stimulate adrenoceptors. Endogenous catecholamines are effective in treating cardiogenic shock. α2-agonists like clonidine can reverse anesthesia-induced hypertension.
Allergies and anaphylaxis:...
01:25Antiasthma Drugs: β2-Adrenoceptor Agonists
One class of bronchodilators includes β2-adrenoceptor agonists. These agents target the β2-adrenoceptors located on bronchial smooth muscle cells. By stimulating these receptors, β2-agonists induce relaxation in these...