Publication Date:
1988-12-09
Description:
Airway epithelial chloride secretion is controlled by the apical-membrane chloride permeability. Purified apical-membrane vesicles from bovine tracheal epithelium have now been shown to contain functional chloride channels by using the planar-bilayer technique. Three types of chloride channels were observed; a voltage-dependent, calcium-independent, 71-picoSiemen (in 150 mM NaCl) channel accounted for more than 80 percent of the vesicular chloride conductance and was under strict control of phosphorylation. The channel underwent a fast rundown in less than 2 to 3 minutes of recording, and reactivation required in situ exposure to a phosphorylating "cocktail" containing the catalytic subunit of the adenosine 3',5'-monophosphate (cAMP)-dependent protein kinase. Mean open time and open probability were increased after phosphorylation, whereas slope conductance remained unchanged. Thus, metabolic control of tracheal chloride single channels can now be studied in vitro.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Valdivia, H H -- Dubinsky, W P -- Coronado, R -- DK 38518/DK/NIDDK NIH HHS/ -- GM 36852/GM/NIGMS NIH HHS/ -- HL 37044/HL/NHLBI NIH HHS/ -- New York, N.Y. -- Science. 1988 Dec 9;242(4884):1441-4.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Physiology and Molecular Biophysics, Baylor College of Medicine, Houston, TX 77030.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/2462280" target="_blank"〉PubMed〈/a〉
Keywords:
Animals
;
Cattle
;
Cell Membrane/physiology
;
Chloride Channels
;
Chlorides/isolation & purification/metabolism/*physiology
;
Electric Conductivity
;
Ion Channels/*physiology
;
Membrane Potentials
;
Membrane Proteins/isolation & purification/metabolism/*physiology
;
Phosphorylation
;
Trachea/*physiology
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
