Am J Physiol Cell Physiol Fuel your research with LabChart
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
QUICK SEARCH:   [advanced]


     

Am J Physiol Cell Physiol (September 3, 2003). doi:10.1152/ajpcell.00194.2003
This Article
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
286/1/C73    most recent
00194.2003v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
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 Google Scholar
Google Scholar
Right arrow Articles by Shtifman, A.
Right arrow Articles by Protasi, F.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Shtifman, A.
Right arrow Articles by Protasi, F.
Submitted on May 12, 2003
Accepted on August 31, 2003

Ca2+ Influx Through {alpha}1s DHPR May Play a Role in Regulating Ca2+ Release from RyR1 in Skeletal Muscle

Alexander Shtifman1*, Cecilia Paolini2, Jose R Lopez3, Paul D Allen1, and Feliciano Protasi4

1 Anesthesia, Brigham and Women's Hospital, Boston, MA, USA
2 Cell and Developmental Biology, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
3 Anesthesia, Brigham and Women's Hospital, Boston, MA, USA; Centro de Biofisica y Bioquimica, Instituto Venezolano de Investigaciones Cientificas, Caracas, Apartado, Venezuela
4 Anesthesia, Brigham and Women's Hospital, Boston, MA, USA; Laboratory of Cellular Physiology, CeSi, Center for Research on Aging, Universityt G. d'Annunzio Schoiol of Medicine, Chienti, Italy

* To whom correspondence should be addressed. E-mail: shtifman{at}zeus.bwh.harvard.edu.

Differentiated primary myotubes isolated from wt mice exhibit ryanodine sensitive, spontaneous global Ca2+ oscillations as well as spontaneous depolarizations in the plasma membrane. Immunolabeling of these myotubes showed expression of both {alpha}1SDHPRs and RyR1, the two key proteins in skeletal excitation-contraction (E-C) coupling. Spontaneous global Ca2+ oscillations could be inhibited by addition of 0.1mM CdCl2/ 0.5mM LaCl3 or 5µM nifedipine to the extracellular bathing solution. After either treatment, Ca2+ oscillations could be restored upon extensive washing. Although exposure to DHPR antagonists completely blocked Ca2+ oscillations, normal orthograde signaling between DHPRs and RyRs, such as that elicited by 80mM KCl depolarization, was still observed. In addition we showed that spontaneous Ca2+ oscillations were never present in cultured mdg myotubes, which lack the expression of {alpha}1SDHPRs. These results suggest that under physiological conditions in conjunction with the mechanical coupling between the {alpha}1SDHPRs and RyR1, the initiation of Ca2+ oscillations in myotubes may be facilitated, in part, by the Ca2+ influx through the {alpha}1s subunit of the DHPR.




This article has been cited by other articles:


Home page
 J. Biol. Chem.Home page
R. A. Christensen, A. Shtifman, P. D. Allen, J. R. Lopez, and H. W. Querfurth
Calcium Dyshomeostasis in {beta}-Amyloid and Tau-bearing Skeletal Myotubes
J. Biol. Chem., December 17, 2004; 279(51): 53524 - 53532.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Cell Physiol.Home page
F. Protasi, A. Shtifman, F. J. Julian, and P. D. Allen
All three ryanodine receptor isoforms generate rapid cooling responses in muscle cells
Am J Physiol Cell Physiol, March 1, 2004; 286(3): C662 - C670.
[Abstract] [Full Text]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
Visit Other APS Journals Online
Copyright © 1976 by the American Physiological Society.