PMID: 6411854Jul 1, 1983Paper

Urea permeability of human red cells

The Journal of General Physiology
J Brahm

Abstract

The rate of unidirectional [14C]urea efflux from human red cells was determined in the self-exchange and net efflux modes with the continuous flow tube method. Self-exchange flux was saturable and followed simple Michaelis-Menten kinetics. At 38 degrees C the maximal self-exchange flux was 1.3 X 10(-7) mol cm-2 s-1, and the urea concentration for half-maximal flux, K1/2, was 396 mM. At 25 degrees C the maximal self-exchange flux decreased to 8.2 X 10(-8) mol cm-2 s-1, and K1/2 to 334 mM. The concentration-dependent urea permeability coefficient was 3 X 10(-4) cm s-1 at 1 mM and 8 X 10(-5) cm s-1 at 800 mM (25 degrees C). The latter value is consonant with previous volumetric determinations of urea permeability. Urea transport was inhibited competitively by thiourea; the half-inhibition constant, Ki, was 17 mM at 38 degrees C and 13 mM at 25 degrees C. Treatment with 1 mM p-chloromercuribenzosulfonate inhibited urea permeability by 92%. Phloretin reduced urea permeability further (greater than 97%) to a "ground" permeability of approximately 10(-6) cm s-1 (25 degrees C). This residual permeability is probably due to urea permeating the hydrophobic core of the membrane by simple diffusion. The apparent activation energy, EA, of u...Continue Reading

Citations

Oct 1, 1994·Magnetic Resonance in Medicine : Official Journal of the Society of Magnetic Resonance in Medicine·M H Nouri-SorkhabiP W Kuchel
Apr 1, 1993·Pflügers Archiv : European journal of physiology·S MartialP Ripoche
Jan 1, 1986·The Journal of Membrane Biology·L W Horn
Jan 1, 1986·The Journal of Membrane Biology·W R Lieb, W D Stein
Jan 1, 1987·The Journal of Membrane Biology·O Fröhlich, S C Jones
Jan 1, 1985·The Journal of Membrane Biology·P L Dorogi, A K Solomon
Jan 1, 1987·The Journal of Membrane Biology·M R Toon, A K Solomon
Feb 1, 2007·The Journal of Membrane Biology·Serena M Bagnasco
Aug 21, 1986·Biochimica Et Biophysica Acta·M R Toon, A K Solomon
Sep 15, 1988·Biochimica Et Biophysica Acta·D M OjciusA K Solomon
Sep 1, 1988·Biochimica Et Biophysica Acta·O Fröhlich, S C Jones
May 1, 1990·Molecular and Biochemical Parasitology·M A ZannerD L Vander Jagt
Mar 20, 2001·Comparative Biochemistry and Physiology. Part A, Molecular & Integrative Physiology·J Ehrenfeld
Dec 7, 2013·Nature Communications·Reginald McNultyMartin B Ulmschneider
May 1, 1987·The Journal of General Physiology·J Brahm, W R Galey
Feb 13, 2009·Nephrology, Dialysis, Transplantation : Official Publication of the European Dialysis and Transplant Association - European Renal Association·Daniel SchneditzJohn T Daugirdas
Jun 1, 1993·The Journal of Clinical Investigation·R M EffrosC Murphy
Jan 1, 1994·The Journal of Clinical Investigation·T L PalloneR L Jamison
Nov 1, 1995·The Journal of Clinical Investigation·J LimD M Kaji
Aug 1, 1992·American Journal of Kidney Diseases : the Official Journal of the National Kidney Foundation·R M HakimT F Parker
Nov 16, 2013·IEEE Transactions on Medical Imaging·Galen D ReedDaniel B Vigneron
May 18, 2007·Biochimica Et Biophysica Acta·Dan ZhaoBaoxue Yang
Jan 1, 1996·Biological Chemistry Hoppe-Seyler·S vom Dahl, D Haussinger
Jan 1, 1995·Transfusion clinique et biologique : journal de la Société française de transfusion sanguine·J P Cartron, P Ripoche
Jan 7, 2018·Pflügers Archiv : European journal of physiology·Friederike Stumpff
Jul 13, 2002·The Journal of Experimental Zoology·M Danielle McDonaldChris M Wood
Apr 12, 2005·American Journal of Physiology. Renal Physiology·Baoxue Yang, Lise Bankir
Apr 4, 2008·American Journal of Physiology. Regulatory, Integrative and Comparative Physiology·T M RodelaP A Wright
Nov 21, 2009·American Journal of Physiology. Gastrointestinal and Liver Physiology·Khalid AbdounHolger Martens
Nov 5, 2011·Journal of Tissue Engineering and Regenerative Medicine·J BrahmR Schmidt
Nov 8, 2013·American Journal of Physiology. Renal Physiology·C Michele NawataThomas L Pannabecker
Oct 9, 1999·The Journal of Biological Chemistry·F Sidoux-WalterP Bailly
Jun 30, 1995·The Journal of Biological Chemistry·B OlivèsP Bailly
Nov 24, 1999·The American Journal of Physiology·H TsukaguchiM A Hediger
May 1, 1988·The American Journal of Physiology·R I Macey, L W Yousef
Jul 21, 2009·The Journal of Experimental Biology·Patricia A Wright, Chris M Wood
Mar 9, 2013·The Journal of Experimental Biology·Jesper Brahm
Sep 10, 1985·Biochimica Et Biophysica Acta·M A Zanner, W R Galey
Aug 27, 1985·Biochimica Et Biophysica Acta·M R ToonA K Solomon

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.