Abstract
1. Single fast-twitch fibres from the extensor digitorum longus muscle of the rat, Rattus norvegicus, and single twitch fibres from the iliofibularis muscle of the cane toad, Bufo marinus, were mechanically skinned and then used to measure maximally Ca2+-activated [( Ca2+] greater than 0.03 mmol l-1) isometric force production, myofibrillar MgATPase activity and fibre stiffness at different sarcomere lengths. MgATP hydrolysis was linked by an enzyme cascade to the oxidation of NADH (nicotinamide adenine dinucleotide, reduced form) and was monitored by a microfluorimetric system. Fibre stiffness was measured from the amplitude of force oscillations generated by small sinusoidal length changes. 2. At sarcomere lengths which were optimal for isometric force production (around 2.7 microns for rat and 2.2 microns for toad fibres) the myofibrillar MgATPase activity (mean +/- S.E.M.) at 21-22 degrees C was found to be 3.80 +/- 0.53 molecules MgATP hydrolysed s-1 per myosin head for eight rat fibres and 6.35 +/- 0.77 s-1 per myosin head for four toad fibres. 3. At sarcomere lengths shorter than 2.7 microns in rat fibres and 2.2 microns in toad fibres, MgATPase and stiffness remained elevated and close to their respective values at 2.7 microns in rat fibres and 2.2 microns in toad fibres even when the isometric force decreased to near zero levels. 4. The dissociation at short sarcomere lengths of myofibrillar MgATPase activity and fibre stiffness from isometric force suggests that the cross-bridge cycle is not greatly affected by double actin filament overlap with the myosin filaments at short sarcomere lengths. Moreover, the results suggest that cross-bridges can be formed by myosin with actin filaments projecting from the nearest Z-line and from the Z-line in the other half of the sarcomere. 5. These results help to reconcile energetic and mechanical data obtained by others at short sarcomere lengths and can be explained within the framework of the sliding filament theory.
Full text
PDFSelected References
These references are in PubMed. This may not be the complete list of references from this article.
- Allen J. D., Moss R. L. Factors influencing the ascending limb of the sarcomere length-tension relationship in rabbit skinned muscle fibres. J Physiol. 1987 Sep;390:119–136. doi: 10.1113/jphysiol.1987.sp016689. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ashley C. C., Moisescu D. G. Effect of changing the composition of the bathing solutions upon the isometric tension-pCa relationship in bundles of crustacean myofibrils. J Physiol. 1977 Sep;270(3):627–652. doi: 10.1113/jphysiol.1977.sp011972. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ashley C. C., Moisescu D. G. Tension changes in isolated bundles of frog and barnacle myofibrils in response to sudden changes in the external free calcium concentration. J Physiol. 1973 Aug;233(1):8P–9P. [PubMed] [Google Scholar]
- Bressler B. H., Clinch N. F. Cross bridges as the major source of compliance in contracting skeletal muscle. Nature. 1975 Jul 17;256(5514):221–222. doi: 10.1038/256221a0. [DOI] [PubMed] [Google Scholar]
- Craig R., Offer G. Axial arrangement of crossbridges in thick filaments of vertebrate skeletal muscle. J Mol Biol. 1976 Apr 5;102(2):325–332. doi: 10.1016/s0022-2836(76)80057-5. [DOI] [PubMed] [Google Scholar]
- Curtin N. A., Gilbert C., Kretzschmar K. M., Wilkie D. R. The effect of the performance of work on total energy output and metabolism during muscular contraction. J Physiol. 1974 May;238(3):455–472. doi: 10.1113/jphysiol.1974.sp010537. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fink R. H., Stephenson D. G., Williams D. A. Potassium and ionic strength effects on the isometric force of skinned twitch muscle fibres of the rat and toad. J Physiol. 1986 Jan;370:317–337. doi: 10.1113/jphysiol.1986.sp015937. [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]
- Gordon A. M., Huxley A. F., Julian F. J. Tension development in highly stretched vertebrate muscle fibres. J Physiol. 1966 May;184(1):143–169. doi: 10.1113/jphysiol.1966.sp007908. [DOI] [PMC free article] [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]
- Griffiths P. J., Güth K., Kuhn H. J., Rüegg J. C. ATPase activity in rapidly activated skinned muscle fibres. Pflugers Arch. 1980 Sep;387(2):167–173. doi: 10.1007/BF00584268. [DOI] [PubMed] [Google Scholar]
- Güth K., Junge J. Low Ca2+ impedes cross-bridge detachment in chemically skinned Taenia coli. Nature. 1982 Dec 23;300(5894):775–776. doi: 10.1038/300775a0. [DOI] [PubMed] [Google Scholar]
- Güth K., Wojciechowski R. Perfusion cuvette for the simultaneous measurement of mechanical, optical and energetic parameters of skinned muscle fibres. Pflugers Arch. 1986 Nov;407(5):552–557. doi: 10.1007/BF00657515. [DOI] [PubMed] [Google Scholar]
- Hayashi Y., Tonomura Y. Dependence of activity of myofibrillar ATPase on sarcomere length and calcium ion concentration. J Biochem. 1968 Jan;63(1):101–118. doi: 10.1093/oxfordjournals.jbchem.a128736. [DOI] [PubMed] [Google Scholar]
- Homsher E., Irving M., Wallner A. High-energy phosphate metabolism and energy liberation associated with rapid shortening in frog skeletal muscle. J Physiol. 1981 Dec;321:423–436. doi: 10.1113/jphysiol.1981.sp013994. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Huxley A. F. Muscular contraction. J Physiol. 1974 Nov;243(1):1–43. [PMC free article] [PubMed] [Google Scholar]
- Huxley H. E. The mechanism of muscular contraction. Science. 1969 Jun 20;164(3886):1356–1365. doi: 10.1126/science.164.3886.1356. [DOI] [PubMed] [Google Scholar]
- INFANTE A. A., KLAUPIKS D., DAVIES R. E. LENGTH, TENSION AND METABOLISM DURING SHORT ISOMETRIC CONTRACTIONS OF FROG SARTORIUS MUSCLES. Biochim Biophys Acta. 1964 Jul 29;88:215–217. doi: 10.1016/0926-6577(64)90171-8. [DOI] [PubMed] [Google Scholar]
- 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]
- Julian F. J., Moss R. L., Sollins M. R. The mechanism for vertebrate striated muscle contraction. Circ Res. 1978 Jan;42(1):2–14. doi: 10.1161/01.res.42.1.2. [DOI] [PubMed] [Google Scholar]
- Julian F. J., Rome L. C., Stephenson D. G., Striz S. The maximum speed of shortening in living and skinned frog muscle fibres. J Physiol. 1986 Jan;370:181–199. doi: 10.1113/jphysiol.1986.sp015929. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kawai M., Güth K., Winnikes K., Haist C., Rüegg J. C. The effect of inorganic phosphate on the ATP hydrolysis rate and the tension transients in chemically skinned rabbit psoas fibers. Pflugers Arch. 1987 Jan;408(1):1–9. doi: 10.1007/BF00581833. [DOI] [PubMed] [Google Scholar]
- Kushmerick M. J., Davies R. E. The chemical energetics of muscle contraction. II. The chemistry, efficiency and power of maximally working sartorius muscles. Appendix. Free energy and enthalpy of atp hydrolysis in the sarcoplasm. Proc R Soc Lond B Biol Sci. 1969 Dec 23;174(1036):315–353. doi: 10.1098/rspb.1969.0096. [DOI] [PubMed] [Google Scholar]
- Lienhard G. E., Secemski I. I. P 1 ,P 5 -Di(adenosine-5')pentaphosphate, a potent multisubstrate inhibitor of adenylate kinase. J Biol Chem. 1973 Feb 10;248(3):1121–1123. [PubMed] [Google Scholar]
- Moisescu D. G. Kinetics of reaction in calcium-activated skinned muscle fibres. Nature. 1976 Aug 12;262(5569):610–613. doi: 10.1038/262610a0. [DOI] [PubMed] [Google Scholar]
- Moisescu D. G., Thieleczek R. Calcium and strontium concentration changes within skinned muscle preparations following a change in the external bathing solution. J Physiol. 1978 Feb;275:241–262. doi: 10.1113/jphysiol.1978.sp012188. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Moss R. L. Sarcomere length-tension relations of frog skinned muscle fibres during calcium activation at short lengths. J Physiol. 1979 Jul;292:177–192. doi: 10.1113/jphysiol.1979.sp012845. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nakayama Y., Yamaguchi M., Watanabe K., Sekine T. Loss of Ca2+-dependent regulation in glycerinated skeletal muscle contraction. Jpn J Physiol. 1983;33(4):559–566. doi: 10.2170/jjphysiol.33.559. [DOI] [PubMed] [Google Scholar]
- PAGE S. G., HUXLEY H. E. FILAMENT LENGTHS IN STRIATED MUSCLE. J Cell Biol. 1963 Nov;19:369–390. doi: 10.1083/jcb.19.2.369. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rüdel R., Taylor S. R. Striated muscle fibers: facilitation of contraction at short lengths by caffeine. Science. 1971 Apr 23;172(3981):387–389. doi: 10.1126/science.172.3981.387. [DOI] [PubMed] [Google Scholar]
- Stephenson D. G., Wendt I. R., Forrest Q. G. Non-uniform ion distributions and electrical potentials in sarcoplasmic regions of skeletal muscle fibres. Nature. 1981 Feb 19;289(5799):690–692. doi: 10.1038/289690a0. [DOI] [PubMed] [Google Scholar]
- Stephenson D. G., Wendt I. R. Length dependence of changes in sarcoplasmic calcium concentration and myofibrillar calcium sensitivity in striated muscle fibres. J Muscle Res Cell Motil. 1984 Jun;5(3):243–272. doi: 10.1007/BF00713107. [DOI] [PubMed] [Google Scholar]
- Stephenson D. G., Williams D. A. Calcium-activated force responses in fast- and slow-twitch skinned muscle fibres of the rat at different temperatures. J Physiol. 1981 Aug;317:281–302. doi: 10.1113/jphysiol.1981.sp013825. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stephenson D. G., Williams D. A. Effects of sarcomere length on the force-pCa relation in fast- and slow-twitch skinned muscle fibres from the rat. J Physiol. 1982 Dec;333:637–653. doi: 10.1113/jphysiol.1982.sp014473. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stephenson D. G., Williams D. A. Slow amphibian muscle fibres become less sensitive to Ca2+ with increasing sarcomere length. Pflugers Arch. 1983 May;397(3):248–250. doi: 10.1007/BF00584366. [DOI] [PubMed] [Google Scholar]
- Takashi R., Putnam S. A fluorimetric method for continuously assaying ATPase: application to small specimens of glycerol-extracted muscle fibers. Anal Biochem. 1979 Jan 15;92(2):375–382. doi: 10.1016/0003-2697(79)90674-2. [DOI] [PubMed] [Google Scholar]
- Taylor S. R., Rüdel R. Striated muscle fibers: inactivation of contraction induced by shortening. Science. 1970 Feb 6;167(3919):882–884. doi: 10.1126/science.167.3919.882. [DOI] [PubMed] [Google Scholar]
- Trombitás K., Tigyi-Sebes A. How actin filament polarity affects crossbridge force in doubly-overlapped insect muscle. J Muscle Res Cell Motil. 1985 Aug;6(4):447–459. doi: 10.1007/BF00712582. [DOI] [PubMed] [Google Scholar]
- Webb M. R., Hibberd M. G., Goldman Y. E., Trentham D. R. Oxygen exchange between Pi in the medium and water during ATP hydrolysis mediated by skinned fibers from rabbit skeletal muscle. Evidence for Pi binding to a force-generating state. J Biol Chem. 1986 Nov 25;261(33):15557–15564. [PubMed] [Google Scholar]
- Yanagida T., Arata T., Oosawa F. Sliding distance of actin filament induced by a myosin crossbridge during one ATP hydrolysis cycle. Nature. 1985 Jul 25;316(6026):366–369. doi: 10.1038/316366a0. [DOI] [PubMed] [Google Scholar]
- Yates L. D., Greaser M. L. Quantitative determination of myosin and actin in rabbit skeletal muscle. J Mol Biol. 1983 Jul 25;168(1):123–141. doi: 10.1016/s0022-2836(83)80326-x. [DOI] [PubMed] [Google Scholar]