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Contractile properties of mouse single muscle fibers, a comparison with amphibian muscle fibers

Edman, Paul LU (2005) In Journal of Experimental Biology 208(10). p.1905-1913
Abstract
Single fibers, 25-40 mu m wide and 0.5-0.7 mm long, were isolated from the flexor digitorum brevis muscle of the mouse. Force and movement were recorded (21-27 degrees C) from the fiber as a whole and, in certain experiments, from a short marked segment that was held at constant length by feedback control. The maximum tetanic force, 368 +/- 57 kN/m(2) (N = 10), was not significantly different from that recorded in frog muscle fibers at equal temperature. However, the rising phase of the tetanus was considerably slower in the mammalian fibers, 202 +/- 20 ms (N = 17) being required to reach 90% of maximum tetanic force as compared with 59 +/- 4 ms (N = 20) in the frog muscle fibers. Similar to the situation in frog muscle fibers, the... (More)
Single fibers, 25-40 mu m wide and 0.5-0.7 mm long, were isolated from the flexor digitorum brevis muscle of the mouse. Force and movement were recorded (21-27 degrees C) from the fiber as a whole and, in certain experiments, from a short marked segment that was held at constant length by feedback control. The maximum tetanic force, 368 +/- 57 kN/m(2) (N = 10), was not significantly different from that recorded in frog muscle fibers at equal temperature. However, the rising phase of the tetanus was considerably slower in the mammalian fibers, 202 +/- 20 ms (N = 17) being required to reach 90% of maximum tetanic force as compared with 59 +/- 4 ms (N = 20) in the frog muscle fibers. Similar to the situation in frog muscle fibers, the force-velocity relation exhibited two distinct curvatures located on either side of a breakpoint near 80% of the isometric force. Maximum speed of shortening was 4.0 +/- 0.3 fiber lengths s(-1) (N = 6). The relationship between tetanic force and sarcomere length was studied between 1.5 and 4.0 mu m sarcomere spacings, based on length-clamp recordings that were free of 'tension creep'. There was a flat maximum (plateau) of the length-tension relation between approximately 2.0 and 2.4 mu m sarcomere lengths. The descending limb of the length-tension relation (linear regression) intersected the length axis (zero force) at 3.88 mu m and reached maximum force at 2.40 mu m sarcomere length. The slope of the descending limb is compatible with a thick filament length of 1.63 mu m and an average thin filament length of 1.10 mu m. These values accord well with recent electron microscope measurements of myofilament length in mammalian muscle. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
length-tension relationship, relationship, force-velocity, mammalian muscle, muscle fiber, muscle contraction
in
Journal of Experimental Biology
volume
208
issue
10
pages
1905 - 1913
publisher
The Company of Biologists Ltd
external identifiers
  • pmid:15879071
  • wos:000229874300018
  • scopus:20444443609
ISSN
1477-9145
DOI
10.1242/jeb.01573
language
English
LU publication?
yes
id
3bcdbb04-a8ec-4ca5-8997-48087d1c6925 (old id 235646)
alternative location
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=15879071&dopt=Abstract
date added to LUP
2007-08-07 12:05:29
date last changed
2017-01-01 04:25:17
@article{3bcdbb04-a8ec-4ca5-8997-48087d1c6925,
  abstract     = {Single fibers, 25-40 mu m wide and 0.5-0.7 mm long, were isolated from the flexor digitorum brevis muscle of the mouse. Force and movement were recorded (21-27 degrees C) from the fiber as a whole and, in certain experiments, from a short marked segment that was held at constant length by feedback control. The maximum tetanic force, 368 +/- 57 kN/m(2) (N = 10), was not significantly different from that recorded in frog muscle fibers at equal temperature. However, the rising phase of the tetanus was considerably slower in the mammalian fibers, 202 +/- 20 ms (N = 17) being required to reach 90% of maximum tetanic force as compared with 59 +/- 4 ms (N = 20) in the frog muscle fibers. Similar to the situation in frog muscle fibers, the force-velocity relation exhibited two distinct curvatures located on either side of a breakpoint near 80% of the isometric force. Maximum speed of shortening was 4.0 +/- 0.3 fiber lengths s(-1) (N = 6). The relationship between tetanic force and sarcomere length was studied between 1.5 and 4.0 mu m sarcomere spacings, based on length-clamp recordings that were free of 'tension creep'. There was a flat maximum (plateau) of the length-tension relation between approximately 2.0 and 2.4 mu m sarcomere lengths. The descending limb of the length-tension relation (linear regression) intersected the length axis (zero force) at 3.88 mu m and reached maximum force at 2.40 mu m sarcomere length. The slope of the descending limb is compatible with a thick filament length of 1.63 mu m and an average thin filament length of 1.10 mu m. These values accord well with recent electron microscope measurements of myofilament length in mammalian muscle.},
  author       = {Edman, Paul},
  issn         = {1477-9145},
  keyword      = {length-tension relationship,relationship,force-velocity,mammalian muscle,muscle fiber,muscle contraction},
  language     = {eng},
  number       = {10},
  pages        = {1905--1913},
  publisher    = {The Company of Biologists Ltd},
  series       = {Journal of Experimental Biology},
  title        = {Contractile properties of mouse single muscle fibers, a comparison with amphibian muscle fibers},
  url          = {http://dx.doi.org/10.1242/jeb.01573},
  volume       = {208},
  year         = {2005},
}