Journal of Applied Physiology Fuel your research with LabChart
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

J Appl Physiol 94: 2423-2432, 2003; doi:10.1152/japplphysiol.00958.2002
8750-7587/03 $5.00
This Article
Right arrow Full Text Free
Right arrow Full Text (PDF) Free
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
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 (11)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Hrbasová, M.
Right arrow Articles by Svoboda, P.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Hrbasová, M.
Right arrow Articles by Svoboda, P.
Vol. 94, Issue 6, 2423-2432, June 2003

Altered myocardial Gs protein and adenylyl cyclase signaling in rats exposed to chronic hypoxia and normoxic recovery

Markéta Hrbasová1, Jiri Novotny1,2, Lucie Hejnová1,2, Frantisek Kolár3,4, Jan Neckár3,4, and Petr Svoboda1,2

1 Faculty of Natural Sciences, Department of Physiology and Developmental Biology, Charles University, Vinicna 7, Prague 2; 2 Biochemistry of Membrane Receptors Group and 3 Department of Developmental Cardiology, Institute of Physiology, Academy of Sciences of the Czech Republic, and 4 Centre for Experimental Cardiovascular Research, Videnska 1083, Prague 4, Czech Republic

The present work has analyzed the consequences of chronic intermittent high-altitude hypoxia for functioning of the G protein-mediated adenylyl cyclase (AC) signaling system in the right (RV) and left ventricular (LV) myocardium in rats. Adaptation to hypoxia did not appreciably affect the number of beta -adrenoceptors and the content of predominantly membrane-bound alpha -subunit (Gsalpha ) of the stimulatory G protein, but it raised the amount of cytosolic Gsalpha in RV. The levels of myocardial inhibitory Galpha protein were not altered. Activity of AC stimulated by GTP, fluoride, forskolin, or isoprotertenol was reduced by ~50% in RV from chronically hypoxic rats, and a weaker depression was also found in LV. In addition, hypoxia significantly diminished a functional activity of membrane-bound Gsalpha in both RV and LV. The RV baseline contractile function was markedly increased in chronically hypoxic animals, and its sensitivity to beta -adrenergic stimulation was decreased. Animals recovering from hypoxia for 5 wk still exhibited markedly elevated levels of cytosolic Gsalpha and significantly lower activity of AC in RV than did age-matched controls, but contractile responsiveness to beta -agonists was normal.

rat myocardium; beta-adrenoceptors; G proteins


This article has been cited by other articles:


Home page
 J. Appl. Physiol.Home page
P. La Padula and L. E. Costa
Effect of sustained hypobaric hypoxia during maturation and aging on rat myocardium. I. Mechanical activity
J Appl Physiol, June 1, 2005; 98(6): 2363 - 2369.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Heart Circ. Physiol.Home page
J. Neckar, I. Markova, F. Novak, O. Novakova, O. Szarszoi, B. Ost'adal, and F. Kolar
Increased expression and altered subcellular distribution of PKC-{delta} in chronically hypoxic rat myocardium: involvement in cardioprotection
Am J Physiol Heart Circ Physiol, April 1, 2005; 288(4): H1566 - H1572.
[Abstract] [Full Text] [PDF]

Home page
 Cardiovasc ResHome page
C. V. Rohlicek, S. Viau, P. Trieu, and T. E. Hebert
Effects of neonatal hypoxia in the rat on inotropic stimulation of the adult heart
Cardiovasc Res, March 1, 2005; 65(4): 861 - 868.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online
Copyright © 2003 by the American Physiological Society.