TACR1 and chronic obstructive pulmonary disease: The overexpression of NK-1R and NK-2R receptors is usually found in inflammatory airway diseases, such as bronchial asthma or chronic obstructive pulmonary disease [35,36], with a role in bronchoconstriction, airway hyperresponsiveness and airway inflammation caused by allergic and nonallergic stimuli, which has prompted the development of both selective and dual-selective NK-1R/NK-2R antagonists that have entered clinic studies with promising results [36,37].