Which mediator is described as an extremely powerful bronchoconstrictor and is involved with asthma and anaphylaxis?

Which mediator is described as an extremely powerful bronchoconstrictor and is involved with asthma and anaphylaxis?

• A. Leukotrienes
• B. Prostaglandins
• C. Interleukins
• D. Histamines

Answer: (A)

The concept being tested is how different inflammatory mediators affect the airways. Leukotrienes are potent lipid mediators produced from arachidonic acid that drive bronchoconstriction and mucus production. In asthma, LTC4, LTD4, and LTE4 (the so-called slow-reacting substances of anaphylaxis) cause strong, sustained narrowing of the airways, contributing to wheezing and breathing difficulty. They also participate in the inflammatory cascade seen in anaphylaxis, helping sustain bronchospasm beyond the immediate reaction. Because of their powerful and lasting effect on the airways, leukotrienes are a key target in asthma therapy (leukotriene receptor antagonists). Histamines trigger rapid bronchoconstriction and are central to immediate allergic reactions and anaphylaxis, but the phrase “extremely powerful bronchoconstrictor” points more to leukotrienes, especially regarding sustained airway narrowing. Prostaglandins can influence bronchial tone as well, but they’re not as central to the question’s described effect. Interleukins are cytokines involved in immune signaling rather than direct bronchoconstrictors.

The concept being tested is how different inflammatory mediators affect the airways. Leukotrienes are potent lipid mediators produced from arachidonic acid that drive bronchoconstriction and mucus production. In asthma, LTC4, LTD4, and LTE4 (the so-called slow-reacting substances of anaphylaxis) cause strong, sustained narrowing of the airways, contributing to wheezing and breathing difficulty. They also participate in the inflammatory cascade seen in anaphylaxis, helping sustain bronchospasm beyond the immediate reaction. Because of their powerful and lasting effect on the airways, leukotrienes are a key target in asthma therapy (leukotriene receptor antagonists).

Histamines trigger rapid bronchoconstriction and are central to immediate allergic reactions and anaphylaxis, but the phrase “extremely powerful bronchoconstrictor” points more to leukotrienes, especially regarding sustained airway narrowing. Prostaglandins can influence bronchial tone as well, but they’re not as central to the question’s described effect. Interleukins are cytokines involved in immune signaling rather than direct bronchoconstrictors.