| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1
Prolonged exercise followed by a
brief period of reduced activity has been shown to result in an
overshoot in maximal sarcoplasmic reticulum (SR)
Ca2+-ATPase activity [maximal velocity
(Vmax)] in rat locomoter muscles (Ferrington
DA, Reijneveld JC, Bär PR, and Bigelow DJ. Biochim Biophys
Acta 1279: 203-213, 1996). To investigate the functional significance and underlying mechanisms for the increase in
Vmax, we analyzed Ca2+-ATPase
activity and Ca2+ uptake in SR vesicles from the fast rat
gastrocnemius muscles after prolonged running (RUN) and after prolonged
running plus 45 min of low-intensity activity (RUN+) or no activity
(REC45) and compared them with controls (Con). Although no differences were observed between RUN and Con, both Vmax and
Ca2+ uptake were higher (P < 0.05) by 43 and 63%, respectively, in RUN+ and by 35 and 34%, respectively, in
REC45. The increase in Vmax was accompanied by
increases (P < 0.05) in the phosphorylated enzyme
intermediate measured by [
-32P]ATP. No differences
between groups for each condition were found for the fluorescent
probes FITC and
(N-cyclohexyl-N1-dimethylamino-
-naphthyl)carbodiimide,
competitive inhibitors of the nucleotide-binding and
Ca2+-binding sites on the enzyme, respectively. Similarly,
no differences for the Ca2+-ATPase were observed between
groups in nitrotyrosine and phosphoserine residues, a measure of
nitrosylation and phosphorylation states, respectively. Western blots
indicated no changes in relative isoform content of sarcoendoplasmic
reticulum (SERCA)1 and SERCA2a. It is concluded that the increase in
Vmax of the Ca2+-ATPase observed in
recovery is not the result of changes in enzyme nitroslyation or
phosphorylation, changes in ATP and Ca2+-binding affinity,
or changes in protein content of the Ca2+-ATPase.
muscle; calcium-adenosinetriphosphatase; calcium uptake; calcium release; vesicles; sarcoplasmic reticulum
This article has been cited by other articles:
|
|
 |
|
  S. Matsunaga, T. Mishima, T. Yamada, S. Inashima, and M. Wada Alterations in in vitro function and protein oxidation of rat sarcoplasmic reticulum Ca2+-ATPase during recovery from high-intensity exercise Exp Physiol, March 1, 2008; 93(3): 426 - 433. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. G. Allen, G. D. Lamb, and H. Westerblad Skeletal Muscle Fatigue: Cellular Mechanisms Physiol Rev, January 1, 2008; 88(1): 287 - 332. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. R. Tupling, C. Vigna, R. J. Ford, S. C. Tsuchiya, D. A. Graham, S. G. Denniss, and J. W. E. Rush Effects of buthionine sulfoximine treatment on diaphragm contractility and SR Ca2+ pump function in rats J Appl Physiol, December 1, 2007; 103(6): 1921 - 1928. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. A. Duhamel, H. J. Green, R. D. Stewart, K. P. Foley, I. C. Smith, and J. Ouyang Muscle metabolic, SR Ca2+-cycling responses to prolonged cycling, with and without glucose supplementation J Appl Physiol, December 1, 2007; 103(6): 1986 - 1998. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 F. Beitzel, M. N. Sillence, and G. S. Lynch beta-Adrenoceptor signaling in regenerating skeletal muscle after beta-agonist administration Am J Physiol Endocrinol Metab, October 1, 2007; 293(4): E932 - E940. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 T. A. Duhamel, H. J. Green, J. G. Perco, and J. Ouyang Comparative effects of a low-carbohydrate diet and exercise plus a low-carbohydrate diet on muscle sarcoplasmic reticulum responses in males Am J Physiol Cell Physiol, October 1, 2006; 291(4): C607 - C617. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. P. Holloway, H. J. Green, and A. R. Tupling Differential effects of repetitive activity on sarcoplasmic reticulum responses in rat muscles of different oxidative potential Am J Physiol Regulatory Integrative Comp Physiol, February 1, 2006; 290(2): R393 - R404. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. D. Schertzer, D. R. Plant, J. G. Ryall, F. Beitzel, N. Stupka, and G. S. Lynch {beta}2-Agonist administration increases sarcoplasmic reticulum Ca2+-ATPase activity in aged rat skeletal muscle Am J Physiol Endocrinol Metab, March 1, 2005; 288(3): E526 - E533. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. A. Leppik, R. J. Aughey, I. Medved, I. Fairweather, M. F. Carey, and M. J. McKenna Prolonged exercise to fatigue in humans impairs skeletal muscle Na+-K+-ATPase activity, sarcoplasmic reticulum Ca2+ release, and Ca2+ uptake J Appl Physiol, October 1, 2004; 97(4): 1414 - 1423. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. A. Duhamel, H. J. Green, J. G. Perco, S. D. Sandiford, and J. Ouyang Human muscle sarcoplasmic reticulum function during submaximal exercise in normoxia and hypoxia J Appl Physiol, July 1, 2004; 97(1): 180 - 187. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. A. Duhamel, H. J. Green, S. D. Sandiford, J. G. Perco, and J. Ouyang Effects of progressive exercise and hypoxia on human muscle sarcoplasmic reticulum function J Appl Physiol, July 1, 2004; 97(1): 188 - 196. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
