AJP - Cell Physiology, Vol 253, Issue 2 C296-C300, Copyright © 1987 by American Physiological Society

ARTICLES

Changes in intracellular ionized Ca concentration associated with muscle fiber type transformation

F. A. Sreter, J. R. Lopez, L. Alamo, K. Mabuchi and J. Gergely

Since increased muscle activity, which results in fast-slow fiber transformation, is associated with increases in sarcoplasmic Ca2+ concentration ([Ca2+]i), it seemed of interest to study the level of [Ca2+] after cessation of stimulation in fibers of the extensor digitorum longus muscle chronically stimulated (8 Hz). [Ca2+]i was measured in individual fibers with a Ca2+-sensitive electrode after subtracting the membrane potential, measured simultaneously from the potential of the Ca2+ electrode. During the first 14 days of stimulation, [Ca2+]i increased from approximately 0.1 to 0.5 microM and declined in approximately 3 wk to a value slightly higher than the initial one. The rise and decline of [Ca2+]i was preceded by a transient increase in total calcium. If stimulation was terminated after 7-8 wk when an essentially complete fast-to-slow transformation had taken place, a subsequent rest period led to a reverse slow-to-fast transformation, which was also preceded by a transient increase of [Ca2+]i reaching a peak at day 5 of rest. Unstimulated fast and slow fibers and fully transformed fibers do not differ in their [Ca2+] levels; thus it appears that the transformation process itself is accompanied, particularly in its earlier stages, by elevated [Ca2+]i levels. Elucidation of the relation between changes in Ca2+ and changes in gene expression will require further work.

This article has been cited by other articles:

				G. Mutungi The expression of NFATc1 in adult rat skeletal muscle fibres Exp Physiol, March 1, 2008; 93(3): 399 - 406. [Abstract] [Full Text] [PDF]

				D. Freyssenet, I. Irrcher, M. K. Connor, M. Di Carlo, and D. A. Hood Calcium-regulated changes in mitochondrial phenotype in skeletal muscle cells Am J Physiol Cell Physiol, May 1, 2004; 286(5): C1053 - C1061. [Abstract] [Full Text] [PDF]

				H.-P. Kubis, N. Hanke, R. J. Scheibe, J. D. Meissner, and G. Gros Ca2+ transients activate calcineurin/NFATc1 and initiate fast-to-slow transformation in a primary skeletal muscle culture Am J Physiol Cell Physiol, July 1, 2003; 285(1): C56 - C63. [Abstract] [Full Text] [PDF]

				H. Gissel and T. Clausen Ca2+ uptake and cellular integrity in rat EDL muscle exposed to electrostimulation, electroporation, or A23187 Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2003; 285(1): R132 - R142. [Abstract] [Full Text] [PDF]

				U. Delling, J. Tureckova, H. W. Lim, L. J. De Windt, P. Rotwein, and J. D. Molkentin A Calcineurin-NFATc3-Dependent Pathway Regulates Skeletal Muscle Differentiation and Slow Myosin Heavy-Chain Expression Mol. Cell. Biol., September 1, 2000; 20(17): 6600 - 6611. [Abstract] [Full Text]

				K. R. Sultan, B. T. Dittrich, and D. Pette Calpain activity in fast, slow, transforming, and regenerating skeletal muscles of rat Am J Physiol Cell Physiol, September 1, 2000; 279(3): C639 - C647. [Abstract] [Full Text] [PDF]

				S. Carroll, P. Nicotera, and D. Pette Calcium transients in single fibers of low-frequency stimulated fast-twitch muscle of rat Am J Physiol Cell Physiol, December 1, 1999; 277(6): C1122 - C1129. [Abstract] [Full Text] [PDF]

				C. P. Ingalls, G. L. Warren, and R. B. Armstrong Intracellular Ca2+ transients in mouse soleus muscle after hindlimb unloading and reloading J Appl Physiol, July 1, 1999; 87(1): 386 - 390. [Abstract] [Full Text] [PDF]

				D. Freyssenet, M. Di Carlo, and D. A. Hood Calcium-dependent Regulation of Cytochrome c Gene Expression in Skeletal Muscle Cells. IDENTIFICATION OF A PROTEIN KINASE C-DEPENDENT PATHWAY J. Biol. Chem., April 2, 1999; 274(14): 9305 - 9311. [Abstract] [Full Text] [PDF]

				E. R. Chin, E. N. Olson, J. A. Richardson, Q. Yang, C. Humphries, J. M. Shelton, H. Wu, W. Zhu, R. Bassel-Duby, and R. S. Williams A calcineurin-dependent transcriptional pathway controls skeletal muscle fiber type Genes & Dev., August 15, 1998; 12(16): 2499 - 2509. [Abstract] [Full Text]

				A. Odermatt, S. Becker, V. K. Khanna, K. Kurzydlowski, E. Leisner, D. Pette, and D. H. MacLennan Sarcolipin Regulates the Activity of SERCA1, the Fast-twitch Skeletal Muscle Sarcoplasmic Reticulum Ca2+-ATPase J. Biol. Chem., May 15, 1998; 273(20): 12360 - 12369. [Abstract] [Full Text] [PDF]

				H.-P. Kubis, E.-A. Haller, P. Wetzel, and G. Gros Adult fast myosin pattern and Ca2+-induced slow myosin pattern in primary skeletal muscle culture PNAS, April 15, 1997; 94(8): 4205 - 4210. [Abstract] [Full Text] [PDF]