|
|
|
|||
| Home Help Feedback Subscriptions Archive Search Table of Contents | ||||
Contraction Dynamics of Flight and Stridulatory Muscles of Tettigoniid Insects
1 School of Biological Sciences, University of California Irvine, CA 92717, U.S.A.
1. Isometric contraction kinetics and force-velocity relations were examined in wing muscles of two tettigoniid insects, Neoconocephalus robustus and N. triops. The muscles were first tergocoxal muscles of the mesothoracic and metathoracic segments. The metathoracic muscle is a flight muscle. The mesothoracic muscle is used in flight and in stridulation.
2. In the field, the wing stroke frequency during stridulation by N. triops is about 100 Hz; the thoracic temperature during singing is about 30 C; and the temperature gradient between the thorax and surround is about 15 C. Published data for N. robustus give the wing-stroke frequency during stridulation as about 200 Hz at a thoracic temperature of 35-40 C. The wing-stroke frequency during flight by both species is approximately 20 Hz at 25 C.
3. The twitch time course is similar in equivalent muscles of the two species. At 35 C the twitch duration (onset to 50% relaxation) is 5.5-6.5 ms for mesothoracic muscles and 11-13 ms for metathoracic ones. Twitch and tetanic tension per unit area are about twice as great in the metathoracic muscles as in the faster, mesothoracic ones.
4. Despite the differences in isometric contraction kinetics, the maximum shortening velocity (Vmax) is similar in mesothoracic and metathoracic wing muscles. Vmax values (lengths per second, 35 C), determined by extrapolation of force-velocity curves, were 10.1 (mesothoracic) and 11.1 (metathoracic) for N. robustus; 12.2 (mesothoracic) and 16.1 (metathoracic) for N. triops. With N. triops, Vmax was also determined from the time taken to re-develop tension following quick release. The values obtained were somewhat higher than from extrapolation of force-velocity curves, but again similar for mesothoracic and metathoracic muscles.
5. Twitch time course becomes more rapid and Vmax increases with increasing temperature. Neither twitch nor tetanic tension is greatly affected by temperature change in the range 25-35 C.
6. As for many other fast muscles, force-velocity plots for these muscles have little curvature. It is suggested that the relative straightness of these plots is a consequence of internal viscosity.
Key words: Muscle, insect, contraction dynamics
Accepted on August 8, 1983
This article has been cited by other articles:
![]() |
E. A. Jones, A. S. Jong, and D. J. Ellerby The effects of acute temperature change on swimming performance in bluegill sunfish Lepomis macrochirus J. Exp. Biol., May 1, 2008; 211(9): 1386 - 1393. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. A. Syme and R. K. Josephson How to Build Fast Muscles: Synchronous and Asynchronous Designs Integr. Comp. Biol., August 1, 2002; 42(4): 762 - 770. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Medler Comparative trends in shortening velocity and force production in skeletal muscles Am J Physiol Regulatory Integrative Comp Physiol, August 1, 2002; 283(2): R368 - R378. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. K. Josephson, J. G. Malamud, and D. R. Stokes The efficiency of an asynchronous flight muscle from a beetle J. Exp. Biol., January 12, 2001; 204(23): 4125 - 4139. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. N. Askew and R. L. Marsh The mechanical power output of the pectoralis muscle of blue-breasted quail (Coturnix chinensis): the in vivo length cycle and its implications for muscle performance J. Exp. Biol., January 11, 2001; 204(21): 3587 - 3600. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. Josephson, J. Malamud, and D. Stokes Asynchronous muscle: a primer J. Exp. Biol., January 9, 2000; 203(18): 2713 - 2722. [Abstract] [PDF] |
||||
![]() |
R. Marsh Contractile properties of muscles used in sound production and locomotion in two species of gray tree frog J. Exp. Biol., January 11, 1999; 202(22): 3215 - 3223. [Abstract] [PDF] |
||||
![]() |
M Girgenrath and R. Marsh Power output of sound-producing muscles in the tree frogs Hyla versicolor and Hyla chrysoscelis J. Exp. Biol., January 11, 1999; 202(22): 3225 - 3237. [Abstract] [PDF] |
||||