HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Willumsen, N J Articles by Boucher, R C Search for Related Content PubMed PubMed Citation Articles by Willumsen, N J Articles by Boucher, R C

Zoophysiological Laboratory A, August Krogh Institute, University of Copenhagen, Denmark.

1. Intracellular pH (pHi) of cultured human airway epithelial cells from normal and cystic fibrosis (CF) subjects were measured with double-barrelled pH-sensitive liquid exchanger microelectrodes. The cells, which were grown to confluence on a permeable collagen matrix support, were mounted in a modified miniature Ussing chamber. All studies were conducted under open circuit conditions. Values are given as means +/- S.E.M. and n refers to the number of preparations. 2. Normal preparations (n = 15) were characterized by a transepithelial potential difference (Vt) of -18 +/- 2 mV, an apical membrane potential (Va) of -19 +/- 2 mV, a basolateral membrane potential (Vb) of -37 +/- 2 mV, a transepithelial resistance (Rt) of 253 +/- 15 omega cm2, a fractional apical membrane resistance (fRa) of 0.40 +/- 0.04 and an equivalent short circuit current (Ieq) of -73 +/- 7 microA cm-2. 3. CF preparations (n = 13) were characterized by a Vt of -46 +/- 7 mV, a Va of 3 +/- 5 mV, a Vb of -43 +/- 3 mV, Rt of 373 +/- 47 omega cm2, fRa of 0.44 +/- 0.04 and an Ieq of -130 +/- 16 microA cm-2. All parameters except Vb and fRa were significantly different (P < 0.025) from those of normal preparations. 4. Despite large differences in electrochemical driving force for proton flow across the apical cell membranes between normal and CF preparations (-4 +/- 3 mV and 20 +/- 7 mV, respectively), pHi was similar (7.15 +/- 0.02 and 7.11 +/- 0.05, respectively). The driving force across the basolateral membrane was similar in normal and CF preparations (22 +/- 3 and 26 +/- 3 mV, respectively). 5. Intracellular alkalinization achieved by removal of CO2 from the luminal Ringer solution or by luminal ammonium prepulse led to stimulation of Ieq in both normal (from -58 to -70 microA cm-2, n = 4; P < 0.05) and CF (from -144 to -163 microA cm-2, n = 4; P < 0.005) preparations. The increase in Ieq was associated with a reduction of Rt, increase in fRa, and hyperpolarization of Vb. All changes in bioelectric properties in response to intracellular alkalinization were fully reversible. 6. Intracellular acidification achieved by serosal ammonium prepulse led to marked reductions of Ieq in both normal (from -95 to -31 microA cm-2, n = 6; P < 0.05) and CF (from -111 to -67 microA cm-2, n = 7; P < 0.005) preparations.(ABSTRACT TRUNCATED AT 400 WORDS)

This article has been cited by other articles:

				S. Blouquit, A. Regnier, L. Dannhoffer, C. Fermanian, E. Naline, R. Boucher, and T. Chinet Ion and Fluid Transport Properties of Small Airways in Cystic Fibrosis Am. J. Respir. Crit. Care Med., August 1, 2006; 174(3): 299 - 305. [Abstract] [Full Text] [PDF]

				M. Mizumori, J. Meyerowitz, T. Takeuchi, S. Lim, P. Lee, C. T. Supuran, P. H. Guth, E. Engel, J. D. Kaunitz, and Y. Akiba Epithelial carbonic anhydrases facilitate PCO2 and pH regulation in rat duodenal mucosa J. Physiol., June 15, 2006; 573(3): 827 - 842. [Abstract] [Full Text] [PDF]

				R. Tarran, L. Trout, S. H. Donaldson, and R. C. Boucher Soluble Mediators, Not Cilia, Determine Airway Surface Liquid Volume in Normal and Cystic Fibrosis Superficial Airway Epithelia J. Gen. Physiol., April 24, 2006; 127(5): 591 - 604. [Abstract] [Full Text] [PDF]

				V. A. Verriere, D. Hynes, S. Faherty, J. Devaney, J. Bousquet, B. J. Harvey, and V. Urbach Rapid Effects of Dexamethasone on Intracellular pH and Na+/H+ Exchanger Activity in Human Bronchial Epithelial Cells J. Biol. Chem., October 28, 2005; 280(43): 35807 - 35814. [Abstract] [Full Text] [PDF]

				R. T. Worrell, A. Best, O. R. Crawford, J. Xu, M. Soleimani, and J. B. Matthews Apical ammonium inhibition of cAMP-stimulated secretion in T84 cells is bicarbonate dependent Am J Physiol Gastrointest Liver Physiol, October 1, 2005; 289(4): G768 - G778. [Abstract] [Full Text] [PDF]

				J. E. Simpson, L. R. Gawenis, N. M. Walker, K. T. Boyle, and L. L. Clarke Chloride conductance of CFTR facilitates basal Cl-/HCO3- exchange in the villous epithelium of intact murine duodenum Am J Physiol Gastrointest Liver Physiol, June 1, 2005; 288(6): G1241 - G1251. [Abstract] [Full Text] [PDF]

				Z. Sutto, G. E Conner, and M. Salathe Regulation of human airway ciliary beat frequency by intracellular pH J. Physiol., October 15, 2004; 560(2): 519 - 532. [Abstract] [Full Text] [PDF]

				C. Schwarzer, T. E. Machen, B. Illek, and H. Fischer NADPH Oxidase-dependent Acid Production in Airway Epithelial Cells J. Biol. Chem., August 27, 2004; 279(35): 36454 - 36461. [Abstract] [Full Text] [PDF]

				R. D. Coakley, B. R. Grubb, A. M. Paradiso, J. T. Gatzy, L. G. Johnson, S. M. Kreda, W. K. O'Neal, and R. C. Boucher Abnormal surface liquid pH regulation by cultured cystic fibrosis bronchial epithelium PNAS, December 23, 2003; 100(26): 16083 - 16088. [Abstract] [Full Text] [PDF]

				J. I. Kourie and A. A. Shorthouse Properties of cytotoxic peptide-formed ion channels Am J Physiol Cell Physiol, June 1, 2000; 278(6): C1063 - C1087. [Abstract] [Full Text] [PDF]

				H. Fischer, J. H. Widdicombe, and B. Illek Acid secretion and proton conductance in human airway epithelium Am J Physiol Cell Physiol, April 1, 2002; 282(4): C736 - C743. [Abstract] [Full Text] [PDF]