Inhibition of chloride secretion in human bronchial epithelial cells by cigarette smoke extract

• Published in: American journal of physiology. Lung cellular and molecular physiology 2005-05, Vol.288 (5), p.L894-L902
• Main Authors: Kreindler, James L, Jackson, Alan D, Kemp, Philip A, Bridges, Robert J, Danahay, Henry
• Format: Article
• Language: English
• Subjects: Bronchi - cytology; Cells, Cultured; Chlorides - metabolism; Electric Capacitance; Electric Conductivity; Electric Impedance; Humans; In Vitro Techniques; Mucins - secretion; Respiratory Mucosa - cytology; Respiratory Mucosa - secretion; Smoking - adverse effects
• ISSN: 1040-0605; 1522-1504
• DOI: 10.1152/ajplung.00376.2004

1 Division of Pediatric Pulmonology, Department of Pediatrics, and 2 Department of Cell Biology and Physiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania; and 3 Novartis Institutes for Biomedical Research, Horsham, United Kingdom Submitted 7 October 2004 ; accepted in final form 27 December 2004 Chronic bronchitis, a disease mainly of cigarette smokers, shares many clinical features with cystic fibrosis, a disease of altered ion transport, suggesting that the negative effects of cigarette smoke on mucociliary clearance may be mediated through alterations in ion transport. We tested the hypothesis that cigarette smoke extract would inhibit chloride secretion in human bronchial epithelial cells. In agreement with studies in canine trachea, cigarette smoke extract inhibited net chloride secretion without affecting sodium transport. We performed microelectrode impalements and impedance analysis studies to investigate the physiological mechanisms of this inhibition. These data demonstrated that cigarette smoke extract caused an acute increase in membrane resistances in conjunction with apical membrane hyperpolarization, an effect consistent with inhibition of an apical membrane anion conductance. After this acute phase, both membrane resistances decreased while membrane potentials continued to hyperpolarize, indicating that cigarette smoke extract also inhibited the basolateral entry of chloride into the cell. Furthermore, cigarette smoke extract caused an increase in mucin secretion. Therefore, the ion transport phenotype of human bronchial epithelial cells exposed to cigarette smoke extract is similar to that of cystic fibrosis epithelia in which there is sodium absorption out of proportion to chloride secretion in the setting of increased mucus secretion. chronic obstructive pulmonary disease; cystic fibrosis; cystic fibrosis transmembrane conductance regulator; airway surface liquid; mucociliary clearance Address for reprint requests and other correspondence: J. L. Kreindler, 3705 Fifth Ave., Pittsburgh, PA 15213 (E-mail: james.kreindler{at}chp.edu )