If a patient experiences a severe asthma exacerbation triggered by histamine release from mast cells, which consequence follows from administering a beta-2 agonist inhaler?

💡 Explanation

Beta-2 agonists stimulate adrenergic receptors on bronchial smooth muscle, leading to smooth muscle relaxation and bronchodilation. This occurs because increased cAMP levels inhibit myosin light-chain kinase activity, thereby reducing bronchospasm; therefore, option D is correct rather than the other options, which would worsen the exacerbation.

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