| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
AJP - Cell Physiology, Vol 262, Issue 2 C411-C417, Copyright © 1992 by American Physiological Society
ARTICLES |
G. F. Tibbits, K. D. Philipson and H. Kashihara
Cardiac Membrane Research Laboratory, Kinesiology, Simon Fraser University, Burnaby, British Columbia, Canada.
This study compared Na(+)-Ca2+ exchange from the hearts of rainbow trout with that from canines. In several respects, trout cardiac Na(+)-Ca2+ exchange is functionally similar to that from dogs and other mammals. Trout cardiac Na(+)-Ca2+ exchange is stimulated approximately 200% after 30-min incubation with 10 micrograms/ml chymotrypsin at 21 degrees C, similar to mammals. On the other hand, both the temperature and pH dependencies are strikingly different between the trout and canine myocardial Na(+)-Ca2+ exchange. While canine heart Na(+)-Ca2+ exchange exhibits a Q10 of greater than 2 (similar to values observed in other mammals), that from trout is relatively insensitive to temperature with a Q10 of approximately 1.2. The absolute rates of Na(+)-Ca2+ exchange in trout heart are four- to sixfold higher than that in mammals when measured at 7 degrees C. Furthermore, the temperature insensitivity of trout myocardial Na(+)-Ca2+ exchange is retained when the exchanger is reconstituted into an asolectin bilayer, suggesting that this property is intrinsic to the protein and not dependent on species differences in lipid bilayer composition. Trout Na(+)-Ca2+ exchange is not markedly stimulated by alkaline pH, in contrast to mammals, and this characteristic is also maintained after reconstitution. Western blots of trout cardiac sarcolemma run on 7.5% sodium dodecyl sulfate-polyacrylamide gel electrophoresis react with antibodies raised against the canine Na(+)-Ca2+ exchanger with a similar pattern of bands (70, 120, and 160 kDa). Furthermore, a cDNA probe from canine Na(+)-Ca2+ exchanger hybridizes on Northern blots of trout heart mRNA to a 7-kb band, similar to that in mammals. Thus, while important functional differences in Na(+)-Ca2+ exchange exist between trout and mammalian hearts, the molecular basis is not yet known.
This article has been cited by other articles:
|
|
 |
|
  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]
|
|
|
|
|
|
L. Hove-Madsen, A. Llach, G. F. Tibbits, and L. Tort Triggering of sarcoplasmic reticulum Ca2+ release and contraction by reverse mode Na+/Ca2+ exchange in trout atrial myocytes Am J Physiol Regulatory Integrative Comp Physiol, May 1, 2003; 284(5): R1330 - R1339. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Maffia, A. Rizzello, R. Acierno, T. Verri, M. Rollo, A. Danieli, F. Doring, H. Daniel, and C. Storelli Characterisation of intestinal peptide transporter of the Antarctic haemoglobinless teleost Chionodraco hamatus J. Exp. Biol., February 15, 2003; 206(4): 705 - 714. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. Marshall, C. Elias, X.-H. Xue, H. D. Le, A. Omelchenko, L. V. Hryshko, and G. F. Tibbits Determinants of cardiac Na+/Ca2+ exchanger temperature dependence: NH2-terminal transmembrane segments Am J Physiol Cell Physiol, August 1, 2002; 283(2): C512 - C520. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. Hove-Madsen, A. Llach, and L. Tort The function of the sarcoplasmic reticulum is not inhibited by low temperatures in trout atrial myocytes Am J Physiol Regulatory Integrative Comp Physiol, December 1, 2001; 281(6): R1902 - R1906. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. L. Elias, X.-H. Xue, C. R. Marshall, A. Omelchenko, L. V. Hryshko, and G. F. Tibbits Temperature dependence of cloned mammalian and salmonid cardiac Na+/Ca2+ exchanger isoforms Am J Physiol Cell Physiol, September 1, 2001; 281(3): C993 - C1000. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. Hove-Madsen, A. Llach, and L. Tort Na+/Ca2+-exchange activity regulates contraction and SR Ca2+ content in rainbow trout atrial myocytes Am J Physiol Regulatory Integrative Comp Physiol, November 1, 2000; 279(5): R1856 - R1864. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. D. Coyne, C. S. Kim, J. S. Cameron, and J. K. Gwathmey Effects of temperature and calcium availability on ventricular myocardium from rainbow trout Am J Physiol Regulatory Integrative Comp Physiol, June 1, 2000; 278(6): R1535 - R1544. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
X.-H. Xue, L. V. Hryshko, D. A. Nicoll, K. D. Philipson, and G. F. Tibbits Cloning, expression, and characterization of the trout cardiac Na+/Ca2+ exchanger Am J Physiol Cell Physiol, October 1, 1999; 277(4): C693 - C700. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. P. Blaustein and W. J. Lederer Sodium/Calcium Exchange: Its Physiological Implications Physiol Rev, July 1, 1999; 79(3): 763 - 854. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. Hove-Madsen and L. Tort L-type Ca2+ current and excitation-contraction coupling in single atrial myocytes from rainbow trout Am J Physiol Regulatory Integrative Comp Physiol, December 1, 1998; 275(6): R2061 - R2069. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. Hove-Madsen, A. Llach, and L. Tort Quantification of Ca2+ uptake in the sarcoplasmic reticulum of trout ventricular myocytes Am J Physiol Regulatory Integrative Comp Physiol, December 1, 1998; 275(6): R2070 - R2080. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
