Explain how the autonomic nerves that innervate the smooth m

Explain how the autonomic nerves that innervate the smooth muscle layer around the bronchioles can influence the volume of air reaching a particular region of the lung.

Solution

Autonomic control of respiration by medullary and pontine centers. Medullary respiratory center has dorsal and ventral group of neurons. Dorsal group of neurons are made-up of primarily I neurons, which discharge during inspiration leads to dilation of the bronchi and the the neurons which are discharged during expiration are E- neurons. The I and E neurons has inhibitory connections with each other i.e.reciprocal innervation. Pontine respiratory center has apneustic center which activates I neurons and pneumotaxic center which activates both I and E neurons. All these group of centers receive affarents from vagus nerve and glossopharyngeal nerve, which also maintains the respiration by constriction and dilation of the bronchi. The parasympathetic stimulation causes cholinergic discharge producing brochoconstriction and increase bronchial secretions. Sympathetic stimulation via adrinergic receptors?causes bronchodilation and increased bronchial secretions. Volume of the air increased when inspiration due to pushing of diaphragm away and filling of the Lungs with air.and opposite happen during the expiration.