Central Autonomic Regulation of the Airways

Postganglionic sympathetic and parasympathetic nerves innervate the airways and lungs of all vertebrates. When activated, these nerves can initiate airway smooth muscle contraction or relaxation, pulmonary or bronchial vascular smooth muscle relaxation and mucus secretion. The often opposing effects of the multiple postganglionic autonomic pathways projecting to the airways and lungs is regulated by many brainstem and midbrain structures. The origin of bronchopulmonary sympathetic and parasympathetic preganglionic nerves are described as are the actions and interactions between brainstem subnuclei controlling autonomic outflow to the airways and the pulmonary and bronchial vasculature.