Mucus secretion is a normal function of respiratory mucous membranes. Models for measurement of mucus production by cultured human and feline bronchial and nasal mucosa have been developed in order to examine the controls of mucus secretion. Two projects were completed. The first defined the distribution and actions of endothelin in the human nasal mucosa, and the second confirmed that the muscarinic M3 receptor is primarily involved in cholinergic regulation of nasal glandular secretion.
