|
|
||||||||
Cystic Fibrosis Research Laboratory, Stanford University, Stanford, California 94305-2130
Submitted 5 April 2004 ; accepted in final form 22 May 2004
We developed a new apparatus, the virtual gland (VG), for measuring the rate of fluid secretion (Jv), its composition, and the transepithelial potential (TEP) in cultured epithelial cells under open circuit. The VG creates a 10-µl chamber above the apical surface of epithelial cells on a Costar filter with a small hole leading to an oil-filled reservoir. After the chamber is primed with a fluid of choice, secreted fluid is forced through the hole into the oil, where it forms a bubble that is monitored optically to determine Jv and collected for analysis. Calu-3 cells were mounted in the VG with a basolateral bath consisting of Krebs-Ringer bicarbonate buffer at 37°C. Basal Jv was 2.7 ± 0.1 µl·cm2·h1 (n = 42), and TEP was 9.2 ± 0.6 mV (n = 33); both measures were reduced to zero by ouabain (n = 6). Jv and TEP were stimulated 64 and 59%, respectively, by 5 µM forskolin (n = 10), 173 and 101% by 1 mM 1-ethyl-2-benzimidazolinone (n = 5), 213 and 122% by 333 nM thapsigargin (n = 5), and 520 and 240% by forskolin + thapsigargin (n = 6). Basal Jv and TEP were inhibited to 82 and 63%, respectively, with 10 µM bumetanide (n = 5), 71 and 82% with 100 µM acetazolamide (n = 5), and 47 and 56% with 600 µM glibenclamide (n = 4). Basal Jv and TEP were 52 and 89% of control values, respectively, after HCO3 replacement with HEPES (n = 16). The net HCO3 concentration of the secreted fluid was close to that of the bath (25 mM), except when stimulated with forskolin or VIP, when it increased (
80 mM). These results validate the use of the VG apparatus and provide the first direct measures of Jv in Calu-3 cells.
cystic fibrosis; submucosal gland; serous cell; mucus; airway
This article has been cited by other articles:
![]() |
D. Wang, Y. Sun, W. Zhang, and P. Huang Apical adenosine regulates basolateral Ca2+-activated potassium channels in human airway Calu-3 epithelial cells Am J Physiol Cell Physiol, June 1, 2008; 294(6): C1443 - C1453. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. R. Dorwart, N. Shcheynikov, D. Yang, and S. Muallem The Solute Carrier 26 Family of Proteins in Epithelial Ion Transport Physiology, April 1, 2008; 23(2): 104 - 114. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Shcheynikov, Y. Wang, M. Park, S. B.H. Ko, M. Dorwart, S. Naruse, P. J. Thomas, and S. Muallem Coupling Modes and Stoichiometry of Cl-/HCO3- Exchange by slc26a3 and slc26a6 J. Gen. Physiol., April 24, 2006; 127(5): 511 - 524. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. J. Wine Acid in the airways. Focus on "Hyperacidity of secreted fluid from submucosal glands in early cystic fibrosis" Am J Physiol Cell Physiol, March 1, 2006; 290(3): C669 - C671. [Full Text] [PDF] |
||||
![]() |
J. V. Wu, M. E. Krouse, A. Rustagi, N. S. Joo, and J. J. Wine An Inwardly Rectifying Potassium Channel in Apical Membrane of Calu-3 Cells J. Biol. Chem., November 5, 2004; 279(45): 46558 - 46565. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |