|
|
||||||||
Department of Medicine, University of Colorado Health Sciences Center, Denver, Colorado 80262
In
cholangiocytes, adenine nucleotides function as autocrine/paracrine
signals that modulate ductular ion transport by activation of
purinergic receptors. The purpose of these studies was to identify cellular signals that modulate ATP release and nucleotide processing in
polarized normal rat cholangiocytes. In Ussing chamber studies, selective exposure of the apical and basolateral membranes to ATP or
adenosine 5'-O-(3-thiotriphosphate) (ATP
S)
stimulated increases in short-circuit current. Apical purinergic
receptor agonist preference was consistent with the P2Y2
subtype. In contrast, basolateral ADP was more potent in stimulating
transepithelial currents, consistent with the expression of different
basolateral P2 receptor(s). Luminometric analysis revealed that both
membranes exhibited constitutive ATP efflux. Hypotonic exposure
enhanced ATP release in both compartments, whereas decreases in ATP
efflux during hypertonicity were more prominent at the apical membrane. Increases in intracellular cAMP, cGMP, and Ca2+ also
increased ATP permeability, but selective effects on apical and
basolateral ATP release differed. Finally, the kinetics of ATP
degradation in apical and basolateral compartments were distinct. These
findings suggest that there are domain-specific signaling pathways that
contribute to purinergic responses in polarized cholangiocytes.
P2 receptors; extracellular nucleotides; adenosine 5'-triphosphate release and processing; transepithelial ion transport
This article has been cited by other articles:
![]() |
A. K. Dutta, A.-k. Khimji, M. Sathe, C. Kresge, V. Parameswara, V. Esser, D. C. Rockey, and A. P. Feranchak Identification and functional characterization of the intermediate-conductance Ca2+-activated K+ channel (IK-1) in biliary epithelium Am J Physiol Gastrointest Liver Physiol, November 1, 2009; 297(5): G1009 - G1018. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. K. Dutta, K. Woo, R. B. Doctor, J. G. Fitz, and A. P. Feranchak Extracellular nucleotides stimulate Cl- currents in biliary epithelia through receptor-mediated IP3 and Ca2+ release Am J Physiol Gastrointest Liver Physiol, November 1, 2008; 295(5): G1004 - G1015. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. I. Masyuk, S. A. Gradilone, J. M. Banales, B. Q. Huang, T. V. Masyuk, S.-O. Lee, P. L. Splinter, A. J. Stroope, and N. F. LaRusso Cholangiocyte primary cilia are chemosensory organelles that detect biliary nucleotides via P2Y12 purinergic receptors Am J Physiol Gastrointest Liver Physiol, October 1, 2008; 295(4): G725 - G734. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Woo, A. K. Dutta, V. Patel, C. Kresge, and A. P. Feranchak Fluid flow induces mechanosensitive ATP release, calcium signalling and Cl- transport in biliary epithelial cells through a PKC{zeta}-dependent pathway J. Physiol., June 1, 2008; 586(11): 2779 - 2798. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. Burnstock Physiology and Pathophysiology of Purinergic Neurotransmission Physiol Rev, April 1, 2007; 87(2): 659 - 797. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. B. Doctor, T. Matzakos, R. McWilliams, S. Johnson, A. P. Feranchak, and J. G. Fitz Purinergic regulation of cholangiocyte secretion: identification of a novel role for P2X receptors Am J Physiol Gastrointest Liver Physiol, April 1, 2005; 288(4): G779 - G786. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Gatof, G. Kilic, and J. G. Fitz Vesicular exocytosis contributes to volume-sensitive ATP release in biliary cells Am J Physiol Gastrointest Liver Physiol, April 1, 2004; 286(4): G538 - G546. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Leipziger Control of epithelial transport via luminal P2 receptors Am J Physiol Renal Physiol, March 1, 2003; 284(3): F419 - F432. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. A. Dranoff, A. I. Masyuk, E. A. Kruglov, N. F. LaRusso, and M. H. Nathanson Polarized expression and function of P2Y ATP receptors in rat bile duct epithelia Am J Physiol Gastrointest Liver Physiol, October 1, 2001; 281(4): G1059 - G1067. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |