AJP - Regu Fuel your research with LabChart
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Am J Physiol Regul Integr Comp Physiol 282: R1191-R1199, 2002; doi:10.1152/ajpregu.00349.2001
0363-6119/02 $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 (14)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Vornanen, M.
Right arrow Articles by Nurmi, A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Vornanen, M.
Right arrow Articles by Nurmi, A.
Vol. 282, Issue 4, R1191-R1199, April 2002

Temperature-dependent expression of sarcolemmal K+ currents in rainbow trout atrial and ventricular myocytes

Matti Vornanen, Ari Ryökkynen, and Antti Nurmi

University of Joensuu, Department of Biology, 80101 Joensuu, Finland

Temperature has a strong influence on the excitability and the contractility of the ectothermic heart that can be alleviated in some species by temperature acclimation. The molecular mechanisms involved in the temperature-induced improvement of cardiac contractility and excitability are, however, still poorly known. The present study examines the role of sarcolemmal K+ currents from rainbow trout (Oncorhynchus mykiss) cardiac myocytes after thermal acclimation. The two major K+ conductances of the rainbow trout cardiac myocytes were identified as the Ba2+-sensitive background inward rectifier current (IK1) and the E-4031-sensitive delayed rectifier current (IKr). In atrial cells, the density of IK1 is very low and the density of IKr is remarkably high. The opposite is true for ventricular cells. Acclimation to cold (4°C) modified the two K+ currents in opposite ways. Acclimation to cold increases the density of IKr and depresses the density of IK1. These changes in repolarizing K+ currents alter the shape of the action potential, which is much shorter in cold-acclimated than warm-acclimated (17°C) trout. These results provide the first concrete evidence that K+ channels of trout cardiac myocytes are adaptable units that provide means to regulate cardiac excitability and contractility as a function of temperature.

inward rectifier; delayed rectifier; thermal acclimation; cardiac myocytes; action potential duration


This article has been cited by other articles:


Home page
 Physiol. GenomicsHome page
B. Rosati, M. Dong, L. Cheng, S.-R. Liou, Q. Yan, J. Y. Park, E. Shiang, M. Sanguinetti, H.-S. Wang, and D. McKinnon
Evolution of ventricular myocyte electrophysiology
Physiol Genomics, November 1, 2008; 35(3): 262 - 272.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
M. Hassinen, J. Haverinen, and M. Vornanen
Electrophysiological properties and expression of the delayed rectifier potassium (ERG) channels in the heart of thermally acclimated rainbow trout
Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2008; 295(1): R297 - R308.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
R. Birkedal and H. A. Shiels
High [Na+]i in cardiomyocytes from rainbow trout
Am J Physiol Regulatory Integrative Comp Physiol, August 1, 2007; 293(2): R861 - R866.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
J. A. W. Stecyk, V. Paajanen, A. P. Farrell, and M. Vornanen
Effect of temperature and prolonged anoxia exposure on electrophysiological properties of the turtle (Trachemys scripta) heart
Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2007; 293(1): R421 - R437.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
M. Hassinen, V. Paajanen, J. Haverinen, H. Eronen, and M. Vornanen
Cloning and expression of cardiac Kir2.1 and Kir2.2 channels in thermally acclimated rainbow trout
Am J Physiol Regulatory Integrative Comp Physiol, June 1, 2007; 292(6): R2328 - R2339.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
J. Haverinen and M. Vornanen
Temperature acclimation modifies sinoatrial pacemaker mechanism of the rainbow trout heart
Am J Physiol Regulatory Integrative Comp Physiol, February 1, 2007; 292(2): R1023 - R1032.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
C. E. Molina, H. Gesser, A. Llach, L. Tort, and L. Hove-Madsen
Modulation of membrane potential by an acetylcholine-activated potassium current in trout atrial myocytes
Am J Physiol Regulatory Integrative Comp Physiol, January 1, 2007; 292(1): R388 - R395.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
M. Vornanen, M. Hassinen, H. Koskinen, and A. Krasnov
Steady-state effects of temperature acclimation on the transcriptome of the rainbow trout heart
Am J Physiol Regulatory Integrative Comp Physiol, October 1, 2005; 289(4): R1177 - R1184.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
H. M. Stauss
Heart rate variability
Am J Physiol Regulatory Integrative Comp Physiol, November 1, 2003; 285(5): R927 - R931.
[Full Text] [PDF]

Home page
 J. Exp. Biol.Home page
H. A. Shiels, M. Vornanen, and A. P. Farrell
Effects of temperature on intracellular [Ca2+] in trout atrial myocytes
J. Exp. Biol., December 1, 2002; 205(23): 3641 - 3650.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
A. Nurmi and M. Vornanen
Electrophysiological properties of rainbow trout cardiac myocytes in serum-free primary culture
Am J Physiol Regulatory Integrative Comp Physiol, April 1, 2002; 282(4): R1200 - R1209.
[Abstract] [Full Text] [PDF]


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