Abstract
The mechanisms and routes by which water is transported across epithelia are debated. It is generally held, and probably true, that the water transport is coupled in a secondary fashion to the transport of ions but the underlying mechanism is not understood at all. So far, most models for transepithelial water transport have been based upon osmotic mechanisms, in which water transport by the cellular route arises from transmembrane osmotic differences. Such models, however, have been unable to explain a number of well-established epithelial properties, for a review see Zeuthen (1992). With the finding that certain membrane proteins function as molecular water pumps, it has been possible to suggest a more general model for transepithelial water transport which would explain, for example, uphill and isotonic transport of water (Zeuthen, 1996andZeuthen, 2000).
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
Boxenbaum N Gether U Klaerke D A and Zeuthen T 2000 Water transport in the Na+/glutamate cotransporter Proc Exp Biol San Diego Abstract
Ikonomov O Simon M and Frömter E 1985 Electrophysiological studies on lateral intercellular spaces of necturus gallbladder epithelium Pflugers Arch 403: 301–307
Loo DDF Zeuthen T Chandy G and Wright EM 1996 Cotransport of water by the Na+/glucose cotransporter Proc Nat Acad SciUSA 93: 13367–13370
Loo DF Hirayama BA Meinild A-K Chandy G Zeuthen T and Wright E 1999 Passive water and ion transport by cotransporters J Physiol 518:195–202
Meinild A-K Loo DDF Pajor A Zeuthen T and Wright E M 2000 Water transport by the renal Na+/dicarboxylate cotransporter Am J Physiol in press
Meinild A-K Klaerke DA Loo DDF Wright EM and Zeuthen T 1998 The human Na+/Glucose cotransporter is a molecular water pump J Physiol 5081: 15–21
Schnermann J Chou C-L Ma T Traynor T Knepper MA and Verkman AS 1998 Defective proximal tubular fluid reabsorbtion in transgenic aquaporin-1 null mice Proc Nat Acad Sci USA 95 9660–9664
Verkmann AS 1999 Lessons on Renal Physiology from Transgenic Mice Lacking Aquaporin Water Channels J Am Soc Nephro 10: 1126–1135
Zeuthen T 2000 Molecular water pumps Rev Physiol Biochem Pharm Springer Verlag pp 97-151 in press
Zeuthen T 1981 Isotonic transport and intracellular osmolarity in the necturus gall-bladder epithelium In Water transport across epithelia (Ussing HH Bindslev N Lassen NA and Sten-Knudsen O eds) Munksgaard Copenhagen pp313–331
Zeuthen T 1982 Relations between intracellular ion activities and extracellular osmolarity in necturus gallbladder epithelium J Membr Biol 66: 109–121
Zeuthen T 1983 Ion activities in the lateral intercellular spaces of gallbladder epithelium transporting at low external osmolarities Jmemb rBiol 76: 113–122
Zeuthen T 1992 From contractile vacuole to leaky epithelia Coupling between salt and water fluxes in biological membranes Biochim Biophys Acta 1113: 229–258
Zeuthen T 1994 Cotransport of K+ Cl- and H20 by membrane proteins from choroid plexus epithelium of Necturus maculosus J Physiol 478: 203–219
Zeuthen T 1995 Molecular mechanisms for passive and active transport of water Int Rev Cytol 160:99–161
Zeuthen T 1996 Molecular Mechanisms of Water Transport Springer Berlin & RG Landes Company pp 170
Zeuthen T Hamann S and La Cour M 1996 Cotransport of H+ lactate and H20 by membrane proteins in retinal pigment epithelium of bullfrog J Physiol 4971: 3–17
Zeuthen T Meinild A-K Klaerke DA Loo DDF Wright EM Belhage B and Litman T 1997 Water transport by the Na+/glucose cotransporter under isotonic conditions Biol Cell 89: 307–312
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2000 Springer Science+Business Media New York
About this chapter
Cite this chapter
Zeuthen, T., Meinild, AK., Loo, D.D.F., Wright, E.M., Klaerke, D.A. (2000). Models for Isotonic Transport Across Apical Membranes of Epithelial Cells. In: Hohmann, S., Nielsen, S. (eds) Molecular Biology and Physiology of Water and Solute Transport. Springer, Boston, MA. https://doi.org/10.1007/978-1-4615-1203-5_27
Download citation
DOI: https://doi.org/10.1007/978-1-4615-1203-5_27
Publisher Name: Springer, Boston, MA
Print ISBN: 978-1-4613-5439-0
Online ISBN: 978-1-4615-1203-5
eBook Packages: Springer Book Archive