Interactions between airway nerves and inflammation

The airways are richly innervated by sensory, parasympathetic, and to a lesser extent, sympathetic nerves. The nerves in the airways assist in maintaining homeostasis in the airways, as well as serving vital defense functions. With respect to defending the airways, the nervous system can lead through coughing, sneezing, and regulation of the inflammatory response. The inflammatory response in the airway leads to the production of various chemical mediators that can excite and modulate airway neurons. Conversely, stimulation of airway neurons can enhance or inhibit various aspects of the inflammatory response. This bidirectional interaction between the nervous system and immune-inflammatory system ideally serves to protect the host, but malfunction in this interactive process may lead to airway inflammatory disease.