Which mediators causing bronchoconstriction are blocked by anticholinergics?

Anticholinergics primarily block the action of acetylcholine, which is a key neurotransmitter involved in the regulation of airway tone, particularly in the bronchial passages. When acetylcholine binds to its receptors on bronchial smooth muscle, it causes contraction, leading to bronchoconstriction. By blocking acetylcholine from binding, anticholinergics help relax the airway smooth muscle and reduce bronchoconstriction, making it easier for patients to breathe.

The correct answer pertains to the mechanisms of bronchoconstriction and how anticholinergic drugs function in the treatment of respiratory conditions such as asthma and chronic obstructive pulmonary disease (COPD). Other mediators like adenosine can also contribute to bronchoconstriction through various pathways, but the primary interaction for anticholinergics is with acetylcholine.

Understanding this mechanism is vital for anyone studying pulmonary medicine, as it highlights the relevance of anticholinergic agents in managing symptoms of airway constriction and their therapeutic implications in respiratory conditions.