Pulmonary Nerve Supply
- Pulmonary nerve supply is mainly autonomic innervation to airway smooth muscle.
- Autonomic fibers control involuntary functions such as airway smooth-muscle tone.
- Bronchial smooth muscle can contract or relax to change airway diameter.
- Bronchiolar smooth muscle is especially important because small changes in diameter strongly affect airflow resistance.
- Axons can also occur in thicker regions of interalveolar septa.
- Parasympathetic nerve activity makes pulmonary smooth muscle contract.
- Contraction of pulmonary smooth muscle narrows airways and increases airflow resistance.
- Sympathetic stimulation relaxes pulmonary smooth muscle.
- Relaxation of pulmonary smooth muscle widens bronchi and bronchioles.
- Bronchodilator drugs mimic sympathetic relaxation to improve airflow.
- Clinical relevance is clear in diseases such as asthma, where airway smooth-muscle tone strongly affects breathing.
Use Hide Bold Terms to cover authored terms, or Hide Every Word to cover every word in the block. Show One reveals the next hidden term or word in reading order without expanding the whole block. In Hide Main, hover a visible term to preview the full bullet.