Abstract
1. A study has been carried out of the tension responses of single fibres from frog semitendinosus muscle at 4 degrees C which occur in response to rapid lengthening and shortening steps throughout the isometric tetanus. 2. Instantaneous stiffness values were calculated as the ratio of the tension change to the length change. 3. Stiffness was seen to increase more rapidly than the tension during the initial development of force and was constant during the tetanus plateau. During the relaxation phase of tension, stiffness declined more slowly than the force up to the shoulder; thereafter both declined rapidly and with a nearly similar time course. 4. Throughout the initial rise of force, the period of maximum force development and the early phase of relaxation, a rapid stretch produced a significantly greater tension change than a rapid release. The fibres appeared 'stiffer' during a stretch. 5. The experimental results are shown to be consistent with the suggestion that cross-bridges may detach during a small rapid shortening step but remain attached during a similar lengthening step.
Full text
PDF










Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Bressler B. H., Clinch N. F. The compliance of contracting skeletal muscle. J Physiol. 1974 Mar;237(3):477–493. doi: 10.1113/jphysiol.1974.sp010493. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bressler B. H., Dusik L. A. A comparison of muscle stiffness measurements obtained with rapid releases or stretches of frog semitendinosus fibers. Adv Exp Med Biol. 1984;170:601–604. doi: 10.1007/978-1-4684-4703-3_55. [DOI] [PubMed] [Google Scholar]
- Cecchi G., Griffiths P. J., Taylor S. The kinetics of cross-bridge attachment and detachment studied by high frequency stiffness measurements. Adv Exp Med Biol. 1984;170:641–655. doi: 10.1007/978-1-4684-4703-3_60. [DOI] [PubMed] [Google Scholar]
- Ford L. E., Huxley A. F., Simmons R. M. Tension responses to sudden length change in stimulated frog muscle fibres near slack length. J Physiol. 1977 Jul;269(2):441–515. doi: 10.1113/jphysiol.1977.sp011911. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ford L. E., Huxley A. F., Simmons R. M. Tension transients during the rise of tetanic tension in frog muscle fibres. J Physiol. 1986 Mar;372:595–609. doi: 10.1113/jphysiol.1986.sp016027. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ford L. E., Huxley A. F., Simmons R. M. The relation between stiffness and filament overlap in stimulated frog muscle fibres. J Physiol. 1981 Feb;311:219–249. doi: 10.1113/jphysiol.1981.sp013582. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Huxley A. F., Simmons R. M. Proposed mechanism of force generation in striated muscle. Nature. 1971 Oct 22;233(5321):533–538. doi: 10.1038/233533a0. [DOI] [PubMed] [Google Scholar]
- Iwazumi T., Pollack G. H. On-line measurement of sarcomere length from diffraction patterns in muscle. IEEE Trans Biomed Eng. 1979 Feb;26(2):86–93. doi: 10.1109/tbme.1979.326514. [DOI] [PubMed] [Google Scholar]
- Julian F. J., Morgan D. L. Variation of muscle stiffness with tension during tension transients and constant velocity shortening in the frog. J Physiol. 1981;319:193–203. doi: 10.1113/jphysiol.1981.sp013901. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Julian F. J., Sollins M. R. Variation of muscle stiffness with force at increasing speeds of shortening. J Gen Physiol. 1975 Sep;66(3):287–302. doi: 10.1085/jgp.66.3.287. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kawai M. Head rotation or dissociation? A study of exponential rate processes in chemically skinned rabbit muscle fibers when MgATP concentration is changed. Biophys J. 1978 Apr;22(1):97–103. doi: 10.1016/S0006-3495(78)85473-3. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schoenberg M., Wells J. B. Stiffness, force, and sarcomere shortening during a twitch in frog semitendinosus muscle bundles. Biophys J. 1984 Feb;45(2):389–397. doi: 10.1016/S0006-3495(84)84163-6. [DOI] [PMC free article] [PubMed] [Google Scholar]
