Skip to main content
PMC home page
Biophysical Journal logoLink to Biophysical Journal
. 1984 Apr;45(4):783–788. doi: 10.1016/S0006-3495(84)84222-8

Radial stiffness of frog skinned muscle fibers in relaxed and rigor conditions.

Y Umazume, N Kasuga
PMCID: PMC1434919  PMID: 6609727

Abstract

Radial stiffness in various conditions of mechanically skinned fibers of semitendinosus muscle of Rana catesbeiana was determined by compressing the fiber with polyvinylpyrrolidone (PVP K-30, Mr = 40,000) in incubating solution. The change in width (D) of fibers with increasing and decreasing PVP concentrations was highly reproducible at a range 0-6% PVP. Radial stiffness of relaxed fibers was almost independent of the sarcomere length. On the other hand, radial stiffness of rigor fibers showed a linear relation against the sarcomere length. These results indicate that cross-bridge attachment would be a major factor in the increase of the radial stiffness. Radial stiffness of relaxed and rigor fibers was (2.14 +/- 0.52) X 10(4) N/m2 (mean +/- SD) and (8.76 +/- 2.04) X 10(4) N/m2, respectively, at the relative fiber width (D/D0) of 0.92, where D0 denotes the fiber width in the rigor solution at 0% PVP. Radial stiffness of a fiber in a rigor solution containing pyrophosphate (PPi) was between those of relaxed and rigor fibers, i.e., (4.76 +/- 0.86) X 10(4) N/m2 at D/Do of 0.92. In PPi and rigor solutions, radial stiffness reversibly increased to around 150 and 130%, respectively, in the presence of 10(-6) M Ca2+. To explain these results, especially the Ca2+-induced change in the radial stiffness, some factor in addition to the number of attached cross-bridges has to be taken into account. The variation of radial stiffness under various conditions will be discussed in relation to the possible manner of cross-bridge attachment.

Full text

PDF
783

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. April E. W., Brandt P. W., Elliott G. F. The myofilament lattice: studies on isolated fibers. I. The constancy of the unit-cell volume with variation in sarcomere length in a lattice in which the thin-to-thick myofilament ratio is 6:1. J Cell Biol. 1971 Oct;51(1):72–82. doi: 10.1083/jcb.51.1.72. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. April E. W., Brandt P. W., Elliott G. F. The myofilament lattice: studies on isolated fibers. II. The effects of osmotic strength, ionic concentration, and pH upon the unit-cell volume. J Cell Biol. 1972 Apr;53(1):53–65. doi: 10.1083/jcb.53.1.53. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Elliott G. F. Force-balances and stability in hexagonally-packed polyelectrolyte systems. J Theor Biol. 1968 Oct;21(1):71–87. doi: 10.1016/0022-5193(68)90060-x. [DOI] [PubMed] [Google Scholar]
  4. Godt R. E., Maughan D. W. Swelling of skinned muscle fibers of the frog. Experimental observations. Biophys J. 1977 Aug;19(2):103–116. doi: 10.1016/S0006-3495(77)85573-2. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Gordon A. M., Huxley A. F., Julian F. J. Tension development in highly stretched vertebrate muscle fibres. J Physiol. 1966 May;184(1):143–169. doi: 10.1113/jphysiol.1966.sp007908. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Huxley H. E. The mechanism of muscular contraction. Science. 1969 Jun 20;164(3886):1356–1365. doi: 10.1126/science.164.3886.1356. [DOI] [PubMed] [Google Scholar]
  7. Kawai M., Brandt P. W. Two rigor states in skinned crayfish single muscle fibers. J Gen Physiol. 1976 Sep;68(3):267–280. doi: 10.1085/jgp.68.3.267. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Magid A., Reedy M. K. X-ray diffraction observations of chemically skinned frog skeletal muscle processed by an improved method. Biophys J. 1980 Apr;30(1):27–40. doi: 10.1016/S0006-3495(80)85074-0. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Matsubara I., Elliott G. F. X-ray diffraction studies on skinned single fibres of frog skeletal muscle. J Mol Biol. 1972 Dec 30;72(3):657–669. doi: 10.1016/0022-2836(72)90183-0. [DOI] [PubMed] [Google Scholar]
  10. Maughan D. W., Godt R. E. Radial forces within muscle fibers in rigor. J Gen Physiol. 1981 Jan;77(1):49–64. doi: 10.1085/jgp.77.1.49. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Maughan D. W., Godt R. E. Stretch and radial compression studies on relaxed skinned muscle fibers of the frog. Biophys J. 1979 Dec;28(3):391–402. doi: 10.1016/S0006-3495(79)85188-7. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Mulvany M. J. Mechanical properties of frog skeletal muscles in iodoacetic acid rigor. J Physiol. 1975 Nov;252(2):319–334. doi: 10.1113/jphysiol.1975.sp011146. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Reedy M. K., Holmes K. C., Tregear R. T. Induced changes in orientation of the cross-bridges of glycerinated insect flight muscle. Nature. 1965 Sep 18;207(5003):1276–1280. doi: 10.1038/2071276a0. [DOI] [PubMed] [Google Scholar]
  14. Rome E. Light and X-ray diffraction studies of the filament lattice of glycerol-extracted rabbit psoas muscle. J Mol Biol. 1967 Aug 14;27(3):591–602. doi: 10.1016/0022-2836(67)90061-7. [DOI] [PubMed] [Google Scholar]
  15. Rome E. X-ray diffraction studies of the filament lattice of striated muscle in various bathing media. J Mol Biol. 1968 Oct 28;37(2):331–344. doi: 10.1016/0022-2836(68)90272-6. [DOI] [PubMed] [Google Scholar]
  16. Thomas D. D., Ishiwata S., Seidel J. C., Gergely J. Submillisecond rotational dynamics of spin-labeled myosin heads in myofibrils. Biophys J. 1980 Dec;32(3):873–889. doi: 10.1016/S0006-3495(80)85023-5. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. White D. C. Rigor contraction and the effect of various phosphate compounds on glycerinated insect flight and vertebrate muscle. J Physiol. 1970 Jul;208(3):583–605. doi: 10.1113/jphysiol.1970.sp009138. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Yoshino S., Umazume Y., Natori R., Fujime S., Chiba S. Optical diffraction study of muscle fibers. II. Electro-optical properties of muscle fibers. Biophys Chem. 1978 Sep;8(4):317–326. doi: 10.1016/0301-4622(78)80014-3. [DOI] [PubMed] [Google Scholar]

Articles from Biophysical Journal are provided here courtesy of The Biophysical Society

RESOURCES