|
|
||||||||
AJP - Cell Physiology, Vol 267, Issue 4 C1136-C1144, Copyright © 1994 by American Physiological Society
ARTICLES |
M. M. Reddy and P. M. Quinton
Division of Biomedical Sciences, University of California, Riverside 92521.
The human sweat duct (SD) reabsorbs NaCl from lumen to blood over a wide range of luminal concentrations. The physiological strategies employed by the SD to cope with such extreme transport loads remain elusive. When we employed intracellular Cl-sensitive microelectrodes, we found that at high (150 mM) luminal NaCl concentrations ([NaCl]) transcellular Cl absorption occurs through passive diffusion that is evidenced by a large Cl conductance (GCl) in both cell membranes and by a favorable electrochemical driving force for Cl (delta psi Cl) across the apical and basolateral membranes. However, lowering the luminal [NaCl] to 15 mM markedly altered the electrochemical gradient for Cl and reversed the direction of delta psi Cl. Under these conditions, passive absorption of Cl was not feasible, so that Cl can only be absorbed by a nonconductive transport carrier. We surmise that, in the face of such changes in delta psi Cl as a function of luminal [NaCl], continuous transcellular Cl transport in SD could only be sustained if both electroconductive and carrier-mediated Cl transport are present in the SD.
This article has been cited by other articles:
![]() |
D. Granger, M. Marsolais, J. Burry, and R. Laprade Na+/H+ exchangers in the human eccrine sweat duct Am J Physiol Cell Physiol, November 1, 2003; 285(5): C1047 - C1058. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. T. Chen and D. B. Yeates Ion transport and regulation of respiratory tract fluid output in dogs J Appl Physiol, March 1, 2001; 90(3): 821 - 831. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. M. Reddy and P. M. Quinton Bumetanide blocks CFTR GCl in the native sweat duct Am J Physiol Cell Physiol, January 1, 1999; 276(1): C231 - C237. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. M. Reddy, R. R. Kopito, and P. M. Quinton Cytosolic pH regulates GCl through control of phosphorylation states of CFTR Am J Physiol Cell Physiol, October 1, 1998; 275(4): C1040 - C1047. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. V. Wu, N. S. Joo, M. E. Krouse, and J. J. Wine Cystic Fibrosis Transmembrane Conductance Regulator Gating Requires Cytosolic Electrolytes J. Biol. Chem., February 23, 2001; 276(9): 6473 - 6478. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |