Abstract
We examined pathways which might result in the elevated resting free calcium [( Ca2+]i) levels observed in dystrophic mouse (mdx) skeletal muscle fibers and myotubes and human Duchenne muscular dystrophy myotubes. We found that mdx fibers, loaded with the calcium indicator fura-2, were less able to regulate [Ca2+]i levels in the region near the sarcolemma. Increased calcium influx or decreased efflux could lead to elevated [Ca2+]i levels. Calcium transient decay times were identical in normal and mdx fibers if resting [Ca2+]i levels were similar, suggesting that calcium-sequestering mechanisms are not altered in dystrophic muscle, but are slowed by the higher resting [Ca2+]i. The defect appears to be specific for calcium since resting free sodium levels and sodium influx rates in the absence of Na+/K(+)- ATPase activity were identical in normal and dystrophic cells when measured with sodium-binding benzofuran isophthalate. Calcium leak channels, whose opening probabilities (Po) were voltage independent, could be the major calcium influx pathway at rest. We have shown previously that calcium leak channel Po is significantly higher in dystrophic myotubes. These leak channels were selective for calcium over sodium under physiological conditions. Agents that increased leak channel activity also increased [Ca2+]i in fibers and myotubes. These results suggest that increased calcium influx, as a result of increased leak channel activity, could result in the elevated [Ca2+]i in dystrophic muscle.
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- Baylor S. M., Hollingworth S. Fura-2 calcium transients in frog skeletal muscle fibres. J Physiol. 1988 Sep;403:151–192. doi: 10.1113/jphysiol.1988.sp017244. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bertorini T. E., Bhattacharya S. K., Palmieri G. M., Chesney C. M., Pifer D., Baker B. Muscle calcium and magnesium content in Duchenne muscular dystrophy. Neurology. 1982 Oct;32(10):1088–1092. doi: 10.1212/wnl.32.10.1088. [DOI] [PubMed] [Google Scholar]
- Bulfield G., Siller W. G., Wight P. A., Moore K. J. X chromosome-linked muscular dystrophy (mdx) in the mouse. Proc Natl Acad Sci U S A. 1984 Feb;81(4):1189–1192. doi: 10.1073/pnas.81.4.1189. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Campbell K. P., Kahl S. D. Association of dystrophin and an integral membrane glycoprotein. Nature. 1989 Mar 16;338(6212):259–262. doi: 10.1038/338259a0. [DOI] [PubMed] [Google Scholar]
- Coulombe A., Lefèvre I. A., Baro I., Coraboeuf E. Barium- and calcium-permeable channels open at negative membrane potentials in rat ventricular myocytes. J Membr Biol. 1989 Oct;111(1):57–67. doi: 10.1007/BF01869209. [DOI] [PubMed] [Google Scholar]
- Desnuelle C., Renaud J. F., Delpont E., Serratrice G., Lazdunski M. [3H]nitrendipine receptors as markers of a class of putative voltage-sensitive Ca2+ channels in normal human skeletal muscle and in muscle from Duchenne muscular dystrophy patients. Muscle Nerve. 1986 Feb;9(2):148–151. doi: 10.1002/mus.880090207. [DOI] [PubMed] [Google Scholar]
- DiMario J., Strohman R. C. Satellite cells from dystrophic (mdx) mouse muscle are stimulated by fibroblast growth factor in vitro. Differentiation. 1988 Nov;39(1):42–49. doi: 10.1111/j.1432-0436.1988.tb00079.x. [DOI] [PubMed] [Google Scholar]
- Duncan C. J. Role of intracellular calcium in promoting muscle damage: a strategy for controlling the dystrophic condition. Experientia. 1978 Dec 15;34(12):1531–1535. doi: 10.1007/BF02034655. [DOI] [PubMed] [Google Scholar]
- Edwards C. The selectivity of ion channels in nerve and muscle. Neuroscience. 1982 Jun;7(6):1335–1366. doi: 10.1016/0306-4522(82)90249-4. [DOI] [PubMed] [Google Scholar]
- Fong C. N., Atwood H. L., Charlton M. P. Intracellular sodium-activity at rest and after tetanic stimulation in muscles of normal and dystrophic (dy2J/dy2J) C57BL/6J mice. Exp Neurol. 1986 Aug;93(2):359–368. doi: 10.1016/0014-4886(86)90196-2. [DOI] [PubMed] [Google Scholar]
- Fong P. Y., Turner P. R., Denetclaw W. F., Steinhardt R. A. Increased activity of calcium leak channels in myotubes of Duchenne human and mdx mouse origin. Science. 1990 Nov 2;250(4981):673–676. doi: 10.1126/science.2173137. [DOI] [PubMed] [Google Scholar]
- Franco A., Jr, Lansman J. B. Calcium entry through stretch-inactivated ion channels in mdx myotubes. Nature. 1990 Apr 12;344(6267):670–673. doi: 10.1038/344670a0. [DOI] [PubMed] [Google Scholar]
- Franco A., Jr, Lansman J. B. Stretch-sensitive channels in developing muscle cells from a mouse cell line. J Physiol. 1990 Aug;427:361–380. doi: 10.1113/jphysiol.1990.sp018176. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Frizzell R. A., Rechkemmer G., Shoemaker R. L. Altered regulation of airway epithelial cell chloride channels in cystic fibrosis. Science. 1986 Aug 1;233(4763):558–560. doi: 10.1126/science.2425436. [DOI] [PubMed] [Google Scholar]
- Grynkiewicz G., Poenie M., Tsien R. Y. A new generation of Ca2+ indicators with greatly improved fluorescence properties. J Biol Chem. 1985 Mar 25;260(6):3440–3450. [PubMed] [Google Scholar]
- Hamill O. P., Marty A., Neher E., Sakmann B., Sigworth F. J. Improved patch-clamp techniques for high-resolution current recording from cells and cell-free membrane patches. Pflugers Arch. 1981 Aug;391(2):85–100. doi: 10.1007/BF00656997. [DOI] [PubMed] [Google Scholar]
- Harootunian A. T., Kao J. P., Eckert B. K., Tsien R. Y. Fluorescence ratio imaging of cytosolic free Na+ in individual fibroblasts and lymphocytes. J Biol Chem. 1989 Nov 15;264(32):19458–19467. [PubMed] [Google Scholar]
- Heizmann C. W., Röhrenbeck J., Kamphuis W. Parvalbumin, molecular and functional aspects. Adv Exp Med Biol. 1990;269:57–66. doi: 10.1007/978-1-4684-5754-4_8. [DOI] [PubMed] [Google Scholar]
- Iaizzo P. A., Seewald M., Oakes S. G., Lehmann-Horn F. The use of Fura-2 to estimate myoplasmic [Ca2+] in human skeletal muscle. Cell Calcium. 1989 Apr;10(3):151–158. doi: 10.1016/0143-4160(89)90069-9. [DOI] [PubMed] [Google Scholar]
- Irving M., Maylie J., Sizto N. L., Chandler W. K. Simultaneous monitoring of changes in magnesium and calcium concentrations in frog cut twitch fibers containing antipyrylazo III. J Gen Physiol. 1989 Apr;93(4):585–608. doi: 10.1085/jgp.93.4.585. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kao J. P., Harootunian A. T., Tsien R. Y. Photochemically generated cytosolic calcium pulses and their detection by fluo-3. J Biol Chem. 1989 May 15;264(14):8179–8184. [PubMed] [Google Scholar]
- Kasai H., Augustine G. J. Cytosolic Ca2+ gradients triggering unidirectional fluid secretion from exocrine pancreas. Nature. 1990 Dec 20;348(6303):735–738. doi: 10.1038/348735a0. [DOI] [PubMed] [Google Scholar]
- Klein M. G., Simon B. J., Szucs G., Schneider M. F. Simultaneous recording of calcium transients in skeletal muscle using high- and low-affinity calcium indicators. Biophys J. 1988 Jun;53(6):971–988. doi: 10.1016/S0006-3495(88)83178-3. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kunze D. L., Ritchie A. K. Multiple conductance levels of the dihydropyridine-sensitive calcium channel in GH3 cells. J Membr Biol. 1990 Nov;118(2):171–178. doi: 10.1007/BF01868474. [DOI] [PubMed] [Google Scholar]
- Martonosi A. Calcium regulation in muscle diseases; the influence of innervation and activity. Biochim Biophys Acta. 1989 May 31;991(2):155–242. doi: 10.1016/0304-4165(89)90110-4. [DOI] [PubMed] [Google Scholar]
- Menke A., Jockusch H. Decreased osmotic stability of dystrophin-less muscle cells from the mdx mouse. Nature. 1991 Jan 3;349(6304):69–71. doi: 10.1038/349069a0. [DOI] [PubMed] [Google Scholar]
- Minta A., Kao J. P., Tsien R. Y. Fluorescent indicators for cytosolic calcium based on rhodamine and fluorescein chromophores. J Biol Chem. 1989 May 15;264(14):8171–8178. [PubMed] [Google Scholar]
- Minta A., Tsien R. Y. Fluorescent indicators for cytosolic sodium. J Biol Chem. 1989 Nov 15;264(32):19449–19457. [PubMed] [Google Scholar]
- Mongini T., Ghigo D., Doriguzzi C., Bussolino F., Pescarmona G., Pollo B., Schiffer D., Bosia A. Free cytoplasmic Ca++ at rest and after cholinergic stimulus is increased in cultured muscle cells from Duchenne muscular dystrophy patients. Neurology. 1988 Mar;38(3):476–480. doi: 10.1212/wnl.38.3.476. [DOI] [PubMed] [Google Scholar]
- Negulescu P. A., Harootunian A., Tsien R. Y., Machen T. E. Fluorescence measurements of cytosolic free Na concentration, influx and efflux in gastric cells. Cell Regul. 1990 Feb;1(3):259–268. doi: 10.1091/mbc.1.3.259. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ohlendieck K., Ervasti J. M., Snook J. B., Campbell K. P. Dystrophin-glycoprotein complex is highly enriched in isolated skeletal muscle sarcolemma. J Cell Biol. 1991 Jan;112(1):135–148. doi: 10.1083/jcb.112.1.135. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rich D. P., Anderson M. P., Gregory R. J., Cheng S. H., Paul S., Jefferson D. M., McCann J. D., Klinger K. W., Smith A. E., Welsh M. J. Expression of cystic fibrosis transmembrane conductance regulator corrects defective chloride channel regulation in cystic fibrosis airway epithelial cells. Nature. 1990 Sep 27;347(6291):358–363. doi: 10.1038/347358a0. [DOI] [PubMed] [Google Scholar]
- Roe M. W., Lemasters J. J., Herman B. Assessment of Fura-2 for measurements of cytosolic free calcium. Cell Calcium. 1990 Feb-Mar;11(2-3):63–73. doi: 10.1016/0143-4160(90)90060-8. [DOI] [PubMed] [Google Scholar]
- Simoneau J. A., Kaufmann M., Härtner K. T., Pette D. Relations between chronic stimulation-induced changes in contractile properties and the Ca2+-sequestering system of rat and rabbit fast-twitch muscles. Pflugers Arch. 1989 Sep;414(6):629–633. doi: 10.1007/BF00582127. [DOI] [PubMed] [Google Scholar]
- Trautmann A., Delaporte C., Marty A. Voltage-dependent channels of human muscle cultures. Pflugers Arch. 1986 Feb;406(2):163–172. doi: 10.1007/BF00586678. [DOI] [PubMed] [Google Scholar]
- Tsien R. Y., Rink T. J. Neutral carrier ion-selective microelectrodes for measurement of intracellular free calcium. Biochim Biophys Acta. 1980 Jul;599(2):623–638. doi: 10.1016/0005-2736(80)90205-9. [DOI] [PubMed] [Google Scholar]
- Turner P. R., Jaffe L. A., Fein A. Regulation of cortical vesicle exocytosis in sea urchin eggs by inositol 1,4,5-trisphosphate and GTP-binding protein. J Cell Biol. 1986 Jan;102(1):70–76. doi: 10.1083/jcb.102.1.70. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Turner P. R., Westwood T., Regen C. M., Steinhardt R. A. Increased protein degradation results from elevated free calcium levels found in muscle from mdx mice. Nature. 1988 Oct 20;335(6192):735–738. doi: 10.1038/335735a0. [DOI] [PubMed] [Google Scholar]
- Williams D. A., Fogarty K. E., Tsien R. Y., Fay F. S. Calcium gradients in single smooth muscle cells revealed by the digital imaging microscope using Fura-2. Nature. 1985 Dec 12;318(6046):558–561. doi: 10.1038/318558a0. [DOI] [PubMed] [Google Scholar]
- Williams D. A., Head S. I., Bakker A. J., Stephenson D. G. Resting calcium concentrations in isolated skeletal muscle fibres of dystrophic mice. J Physiol. 1990 Sep;428:243–256. doi: 10.1113/jphysiol.1990.sp018210. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Zubrzycka-Gaarn E. E., Bulman D. E., Karpati G., Burghes A. H., Belfall B., Klamut H. J., Talbot J., Hodges R. S., Ray P. N., Worton R. G. The Duchenne muscular dystrophy gene product is localized in sarcolemma of human skeletal muscle. Nature. 1988 Jun 2;333(6172):466–469. doi: 10.1038/333466a0. [DOI] [PubMed] [Google Scholar]