Brush Biopsy and Culture of Airway Epithelial Cells: -Adrenergic Receptor System Function

Stimulation by catecholamine agonists of the β-adrenergic coupled adenylyl cyclase (βAR-AC) system, expressed on human tracheobronchial epithelial cells (ECs), elicits a variety of cellular responses that favorably affect airway function, the intensity of the inflammatory reaction, and even the integrity of the epithelial lining (1 –6 ). For example, β-agonist-stimulated production of second messenger, cyclic adenosine monophosphate (cAMP), enhances salt and water exchange (2 ), ciliary beating (3 ), mucus secretion by goblet cells (1 ,4 ), proliferation of airway ECs (5 ), and protection against free radical induced injury (6 ).