Histamine, leukotrienes, and acetylcholine are involved in which airway response?

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Multiple Choice

Histamine, leukotrienes, and acetylcholine are involved in which airway response?

These mediators drive the narrowing of the airways by constricting the smooth muscle around the bronchi. Histamine released from mast cells binds to H1 receptors on airway smooth muscle, causing contraction and also promoting swelling and mucus production. Leukotrienes C4, D4, and E4 are very potent bronchoconstrictors that also increase vascular permeability and mucus, further narrowing the lumen. Acetylcholine, released from parasympathetic nerves, activates M3 muscarinic receptors on smooth muscle, triggering contraction and increasing mucus secretion. Put together, they produce bronchoconstriction—the immediate airway narrowing you see in allergic or inflammatory responses.

These mediators drive the narrowing of the airways by constricting the smooth muscle around the bronchi. Histamine released from mast cells binds to H1 receptors on airway smooth muscle, causing contraction and also promoting swelling and mucus production. Leukotrienes C4, D4, and E4 are very potent bronchoconstrictors that also increase vascular permeability and mucus, further narrowing the lumen. Acetylcholine, released from parasympathetic nerves, activates M3 muscarinic receptors on smooth muscle, triggering contraction and increasing mucus secretion. Put together, they produce bronchoconstriction—the immediate airway narrowing you see in allergic or inflammatory responses.

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