+1 Recommend
0 collections
      • Record: found
      • Abstract: found
      • Article: not found

      Autocrine signaling through ATP release represents a novel mechanism for cell volume regulation.

      Proceedings of the National Academy of Sciences of the United States of America

      analogs & derivatives, metabolism, pharmacology, Animals, Apyrase, Cell Membrane, physiology, Chloride Channels, Chlorides, Hypotonic Solutions, Tumor Cells, Cultured, Kinetics, Liver Neoplasms, Experimental, pathology, physiopathology, Models, Biological, Rats, Receptors, Purinergic P2, drug effects, Signal Transduction, Suramin, Adenosine Triphosphate

      Read this article at

          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.


          Recovery of cell volume in response to osmotic stress is mediated in part by increases in the Cl- permeability of the plasma membrane. These studies evaluate the hypothesis that ATP release and autocrine stimulation of purinergic (P2) receptors couple increases in cell volume to opening of Cl- channels. In HTC rat hepatoma cells, swelling induced by hypotonic exposure increased membrane Cl- current density to 44.8 +/- 7.1 pA/pF at -80 mV. Both the rate of volume recovery and the increase in Cl- permeability were inhibited in the presence of the ATP hydrolase apyrase (3 units/ml) or by exposure to the P2 receptor blockers suramin and Reactive Blue 2 (10-100 microM). Cell swelling also stimulated release of ATP. Hypotonic exposure increased the concentration of ATP in the effluent of perfused cells by 170 +/- 36 nM in the presence of a nucleotidase inhibitor (P < 0.01). In whole-cell recordings with ATP as the charge carrier, cell swelling increased membrane current density approximately 30-fold to 16.5 +/- 10.4 pA/pF. These findings indicate that increases in cell volume lead to efflux of ATP through opening of a conductive pathway consistent with a channel, and that extracellular ATP is required for recovery from swelling. ATP may function as an autocrine factor that couples increases in cell volume to opening of Cl- channels through stimulation of P2 receptors.

          Related collections

          Author and article information



          Comment on this article