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. 1985 Feb;359:357–363. doi: 10.1113/jphysiol.1985.sp015589

Shortening velocity extrapolated to zero load and unloaded shortening velocity of whole rat skeletal muscle.

D R Claflin, J A Faulkner
PMCID: PMC1193379  PMID: 3999042

Abstract

The shortening velocity at zero load (Vmax) extrapolated from velocities measured during isotonic releases was compared with unloaded shortening velocity (V0) determined by the slack test. Experiments were performed in vitro at 20 degrees C on soleus muscles from rats. The Vmax was 3.2 +/- 0.1 (mean +/- S.E. of mean, n = 10) fibre lengths/s while the V0 determined for the same muscles was 5.0 +/- 0.1 fibre lengths/s. The ratio of V0/Vmax was 1.6 +/- 0.1. Soleus muscles of the rat are heterogeneous with respect to the intrinsic shortening velocities of their fibres. The results suggest that V0 is a measure of the unloaded shortening velocity of the fastest fibres whereas Vmax is a function of the force-velocity characteristics of all the fibres within a skeletal muscle preparation.

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Selected References

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

  1. Butler T. M., Siegman M. J., Mooers S. U., Barsotti R. J. Myosin light chain phosphorylation does not modulate cross-bridge cycling rate in mouse skeletal muscle. Science. 1983 Jun 10;220(4602):1167–1169. doi: 10.1126/science.6857239. [DOI] [PubMed] [Google Scholar]
  2. CLOSE R. DYNAMIC PROPERTIES OF FAST AND SLOW SKELETAL MUSCLES OF THE RAT DURING DEVELOPMENT. J Physiol. 1964 Sep;173:74–95. doi: 10.1113/jphysiol.1964.sp007444. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Cleland W. W. The statistical analysis of enzyme kinetic data. Adv Enzymol Relat Areas Mol Biol. 1967;29:1–32. doi: 10.1002/9780470122747.ch1. [DOI] [PubMed] [Google Scholar]
  4. Close R. I. Dynamic properties of mammalian skeletal muscles. Physiol Rev. 1972 Jan;52(1):129–197. doi: 10.1152/physrev.1972.52.1.129. [DOI] [PubMed] [Google Scholar]
  5. Close R. Properties of motor units in fast and slow skeletal muscles of the rat. J Physiol. 1967 Nov;193(1):45–55. doi: 10.1113/jphysiol.1967.sp008342. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Close R. The relation between intrinsic speed of shortening and duration of the active state of muscle. J Physiol. 1965 Oct;180(3):542–559. doi: 10.1113/jphysiol.1965.sp007716. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Crow M. T., Kushmerick M. J. Phosphorylation of myosin light chains in mouse fast-twitch muscle associated with reduced actomyosin turnover rate. Science. 1982 Aug 27;217(4562):835–837. doi: 10.1126/science.6285472. [DOI] [PubMed] [Google Scholar]
  8. Edman K. A. The velocity of unloaded shortening and its relation to sarcomere length and isometric force in vertebrate muscle fibres. J Physiol. 1979 Jun;291:143–159. doi: 10.1113/jphysiol.1979.sp012804. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Gulati J., Babu A. Intrinsic shortening speed of temperature-jump-activated intact muscle fibers. Effects of varying osmotic pressure with sucrose and KCl. Biophys J. 1984 Feb;45(2):431–445. doi: 10.1016/S0006-3495(84)84166-1. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Julian F. J., Morgan D. L. Tension, stiffness, unloaded shortening speed and potentiation of frog muscle fibres at sarcomere lengths below optimum. J Physiol. 1981;319:205–217. doi: 10.1113/jphysiol.1981.sp013902. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Julian F. J., Moss R. L. Effects of calcium and ionic strength on shortening velocity and tension development in frog skinned muscle fibres. J Physiol. 1981 Feb;311:179–199. doi: 10.1113/jphysiol.1981.sp013580. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Kugelberg E. Adaptive transformation of rat soleus motor units during growth. J Neurol Sci. 1976 Mar;27(3):269–289. doi: 10.1016/0022-510x(76)90001-0. [DOI] [PubMed] [Google Scholar]
  13. Lännergren J., Lindblom P., Johansson B. Contractile properties of two varieties of twitch muscle fibres in Xenopus laevis. Acta Physiol Scand. 1982 Apr;114(4):523–535. doi: 10.1111/j.1748-1716.1982.tb07020.x. [DOI] [PubMed] [Google Scholar]
  14. Moss R. L. The effect of calcium on the maximum velocity of shortening in skinned skeletal muscle fibres of the rabbit. J Muscle Res Cell Motil. 1982 Sep;3(3):295–311. doi: 10.1007/BF00713039. [DOI] [PubMed] [Google Scholar]
  15. Reiser P. J., Stokes B. T., Rall J. A. Isometric contractile properties and velocity of shortening during avian myogenesis. Am J Physiol. 1982 Sep;243(3):C177–C183. doi: 10.1152/ajpcell.1982.243.3.C177. [DOI] [PubMed] [Google Scholar]

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