Am J Physiol Cell Physiol Add DOIs to your references at manuscript stage!
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Am J Physiol Cell Physiol 281: C972-C981, 2001;
0363-6143/01 $5.00
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via ISI Web of Science (15)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Churchill, G. C.
Right arrow Articles by Louis, C. F.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Churchill, G. C.
Right arrow Articles by Louis, C. F.
Vol. 281, Issue 3, C972-C981, September 2001

Ca2+ regulation of gap junctional coupling in lens epithelial cells

Grant C. Churchill, Monica M. Lurtz, and Charles F. Louis

Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455

The quantitative effects of Ca2+ signaling on gap junctional coupling in lens epithelial cells have been determined using either the spread of Mn2+ that is imaged by its ability to quench the fluorescence of fura 2 or the spread of the fluorescent dye Alexa Fluor 594. Gap junctional coupling was unaffected by a mechanically stimulated cell-to-cell Ca2+ wave. Furthermore, when cytosolic Ca2+ concentration (Ca<UP><SUB>i</SUB><SUP>2+</SUP></UP>) increased after the addition of the agonist ATP, coupling was unaffected during the period that Ca<UP><SUB>i</SUB><SUP>2+</SUP></UP> was maximal. However, coupling decreased transiently ~5-10 min after agonist addition when Ca<UP><SUB>i</SUB><SUP>2+</SUP></UP> returned to resting levels, indicating that this transient decrease in coupling was unlikely due to a direct action of Ca<UP><SUB>i</SUB><SUP>2+</SUP></UP> on gap junctions. An increase in Ca<UP><SUB>i</SUB><SUP>2+</SUP></UP> mediated by the ionophore ionomycin that was sustained for several minutes resulted in a more rapid and sustained decrease in coupling (IC50 ~300 nM Ca2+, Hill coefficient of 4), indicating that an increase in Ca<UP><SUB>i</SUB><SUP>2+</SUP></UP> alone could regulate gap junctions. Thus Ca<UP><SUB>i</SUB><SUP>2+</SUP></UP> increases that occurred during agonist stimulation and cell-to-cell Ca2+ waves were too transient to mediate a sustained uncoupling of lens epithelial cells.

calcium; gap junction; manganese quench; fura 2


This article has been cited by other articles:


Home page
 Am. J. Physiol. Cell Physiol.Home page
M. M. Lurtz and C. F. Louis
Intracellular calcium regulation of connexin43
Am J Physiol Cell Physiol, December 1, 2007; 293(6): C1806 - C1813.
[Abstract] [Full Text] [PDF]

Home page
 J. Biol. Chem.Home page
Y. Zhou, W. Yang, M. M. Lurtz, Y. Ye, Y. Huang, H.-W. Lee, Y. Chen, C. F. Louis, and J. J. Yang
Identification of the Calmodulin Binding Domain of Connexin 43
J. Biol. Chem., November 30, 2007; 282(48): 35005 - 35017.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Cell Physiol.Home page
M. M. Lurtz and C. F. Louis
Calmodulin and protein kinase C regulate gap junctional coupling in lens epithelial cells
Am J Physiol Cell Physiol, December 1, 2003; 285(6): C1475 - C1482.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online