Journal article
Basolateral chloride current in human airway epithelia
American journal of physiology. Lung cellular and molecular physiology, Vol.293(4), pp.L991-999
10/2007
DOI: 10.1152/ajplung.00077.2007
PMID: 17660331
Abstract
Electrolyte transport by airway epithelia regulates the quantity and composition of liquid covering the airways. Previous data indicate that airway epithelia can absorb NaCl. At the apical membrane, cystic fibrosis transmembrane conductance regulator (CFTR) provides a pathway for Cl(-) absorption. However, the pathways for basolateral Cl(-) exit are not well understood. Earlier studies, predominantly in cell lines, have reported that the basolateral membrane contains a Cl(-) conductance. However, the properties have varied substantially in different epithelia. To better understand the basolateral Cl(-) conductance in airway epithelia, we studied primary cultures of well-differentiated human airway epithelia. The basolateral membrane contained a Cl(-) current that was inhibited by 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS). The current-voltage relationship was nearly linear, and the halide selectivity was Cl(-) > Br(-) >> I(-). Several signaling pathways increased the current, including elevation of cellular levels of cAMP, activation of protein kinase C (PKC), and reduction of pH. In contrast, increasing cell Ca(2+) and inducing cell swelling had no effect. The basolateral Cl(-) current was present in both cystic fibrosis (CF) and non-CF airway epithelia. Likewise, airway epithelia from wild-type mice and mice with disrupted genes for ClC-2 or ClC-3 all showed similar Cl(-) currents. These data suggest that the basolateral membrane of airway epithelia possesses a Cl(-) conductance that is not due to CFTR, ClC-2, or ClC-3. Its regulation by cAMP and PKC signaling pathways suggests that coordinated regulation of Cl(-) conductance in both apical and basolateral membranes may be important in controlling transepithelial Cl(-) movement.
Details
- Title: Subtitle
- Basolateral chloride current in human airway epithelia
- Creators
- Omar A Itani - Howard Hughes Medical Institute, Univ. of Iowa, Iowa City, IA 52242, USAFred S LambJames E MelvinMichael J Welsh
- Resource Type
- Journal article
- Publication Details
- American journal of physiology. Lung cellular and molecular physiology, Vol.293(4), pp.L991-999
- Publisher
- United States
- DOI
- 10.1152/ajplung.00077.2007
- PMID
- 17660331
- ISSN
- 1040-0605
- eISSN
- 1522-1504
- Grant note
- HL61234 / NHLBI NIH HHS DE09692 / NIDCR NIH HHS HL51670 / NHLBI NIH HHS HL62483 / NHLBI NIH HHS
- Language
- English
- Date published
- 10/2007
- Academic Unit
- Neurology; Molecular Physiology and Biophysics; Pulmonary, Critical Care, and Occupational Medicine; Neurosurgery; Internal Medicine
- Record Identifier
- 9984020502902771
Metrics
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