Abstract
The length-tension relationship was determined for strips of guinea pig taenia coli and correlated with the length and ultrastructural organization of the component fibers. The mean fiber length in "stretched" strips (passive ≥ active tension) was 30% greater than that for fibers in "unstretched" strips (active >> passive tension). In stretched fibers the dense bodies and 100 A diameter myofilaments were consolidated into a mass near the center of fibers in cross-sectional profile. The thick myofilaments were segregated into the periphery of the fiber profiles. In unstretched fibers the dense bodies-100 A diameter filaments and the thick myofilaments were uniformly distributed throughout cross-sectional profiles. A tentative model is proposed to account for the change in fiber length and ultrastructural organization that accompanies stretch. The basic features of the model require the dense bodies to be linked together into a network by the 100 A diameter filaments. The functional consequences of stretching the fibers are discussed in relation to the model proposed for this network.
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- CSAPO A., GOODALL M. Excitability, length tension relation and kinetics of uterine muscle contraction in relation to hormonal status. J Physiol. 1954 Nov 29;126(2):384–395. doi: 10.1113/jphysiol.1954.sp005216. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Cooke P. H., Chase R. H. Potassium chloride-insoluble myofilaments in vertebrate smooth muscle cells. Exp Cell Res. 1971 Jun;66(2):417–425. doi: 10.1016/0014-4827(71)90696-3. [DOI] [PubMed] [Google Scholar]
- Gordon A. M., Huxley A. F., Julian F. J. The variation in isometric tension with sarcomere length in vertebrate muscle fibres. J Physiol. 1966 May;184(1):170–192. doi: 10.1113/jphysiol.1966.sp007909. [DOI] [PMC free article] [PubMed] [Google Scholar]
- HUXLEY A. F., PEACHEY L. D. The maximum length for contraction in vertebrate straiated muscle. J Physiol. 1961 Apr;156:150–165. doi: 10.1113/jphysiol.1961.sp006665. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lane B. P. Alterations in the cytologic detail of intestinal smooth muscle cells in various stages of contraction. J Cell Biol. 1965 Oct;27(1):199–213. doi: 10.1083/jcb.27.1.199. [DOI] [PMC free article] [PubMed] [Google Scholar]
- PEASE D. C., MOLINARI S. Electron microscopy of muscular arteries; pial vessels of43 the cat and monkey. J Ultrastruct Res. 1960 Jun;3:447–468. doi: 10.1016/s0022-5320(60)90022-8. [DOI] [PubMed] [Google Scholar]
- Panner B. J., Honig C. R. Filament ultrastructure and organization in vertebrate smooth muscle. Contraction hypothesis based on localization of actin and myosin. J Cell Biol. 1967 Nov;35(2):303–321. doi: 10.1083/jcb.35.2.303. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rice R. V., Moses J. A., McManus G. M., Brady A. C., Blasik L. M. The organization of contractile filaments in a mammalian smooth muscle. J Cell Biol. 1970 Oct;47(1):183–196. doi: 10.1083/jcb.47.1.183. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Somlyo A. P., Somlyo A. V., Devine C. E., Rice R. V. Aggregation of thick filaments into ribbons in mammalian smooth muscle. Nat New Biol. 1971 Jun 23;231(25):243–246. doi: 10.1038/newbio231243a0. [DOI] [PubMed] [Google Scholar]
- Stephens N. L., Kroeger E., Mehta J. A. Force-velocity characteristics of respiratory airway smooth muscle. J Appl Physiol. 1969 Jun;26(6):685–692. doi: 10.1152/jappl.1969.26.6.685. [DOI] [PubMed] [Google Scholar]
- Szent-Györgyi A. G., Cohen C., Kendrick-Jones J. Paramyosin and the filaments of molluscan "catch" muscles. II. Native filaments: isolation and characterization. J Mol Biol. 1971 Mar 14;56(2):239–258. doi: 10.1016/0022-2836(71)90462-1. [DOI] [PubMed] [Google Scholar]