In an asthma exacerbation treated with a beta-2 agonist inhaler, what distinguishes the bronchodilation mechanism from simple airway relaxation?

💡 Explanation

Beta-2 agonists stimulate bronchodilation via increased intracellular cAMP in smooth muscle cells, because the agonist binds to beta-2 receptors, activating adenylyl cyclase. Therefore, the outcome is smooth muscle relaxation, rather than a direct blockage or reduced mucus; those are secondary or unrelated effects.

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