These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Swelling-activated anion conductance in skate hepatocytes: regulation by cell Cl- and ATP.
    Author: Jackson PS, Churchwell K, Ballatori N, Boyer JL, Strange K.
    Journal: Am J Physiol; 1996 Jan; 270(1 Pt 1):C57-66. PubMed ID: 8772430.
    Abstract:
    Cell swelling activates an outwardly rectifying anion conductance in mammalian cells. The channel responsible for this conductance mediates volume-regulatory efflux of organic osmolytes such as taurine. We observed a similar conductance in hepatocytes from the skate Raja erinacea. Whole cell Cl- conductance was increased > 100-fold by a 2-fold increase in hepatocyte volume. The conductance was outwardly rectifying and had a relative cation permeability of approximately 0.2. Cation permeability was increased by reductions in patch pipette CsCl concentration, suggesting that the channel pore contains saturable anion and cation binding sites with different anion and cation affinities. The conductance had a broad anion selectivity and a relative taurine permeability of 0.17. Activation of the conductance required intracellular ATP or a nonhydrolyzable ATP analogue. Elevation of intracellular Cl- from 20 to 155 mM reduced current activation while the rate and extent of cell swelling were unaffected. Reduction of intracellular Cl- concentration to 5-10 mM caused spontaneous current activation without cell swelling. These results suggest that increases in cell Cl- levels increase the volume set point of the channel. We propose that the main function of the outwardly rectifying anion channel is nonselective transport of organic solutes.
    [Abstract] [Full Text] [Related] [New Search]