Ca‐, Sr‐tension relationships and contraction velocities of human muscle fibers

Ruff, Robert L.; Whittlesey, Diana

doi:10.1002/mus.880141214

Cited by 19 publications

(18 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Close relationships between Vmax and myosin heavy chain (MHC) composition have been demonstrated in single fibres from crustacean (Galler & Rathmayer, 1992), amphibian (Liinnergren & Hoh, 1984;Liinnergren, 1987;Edman, Reggiani, Schiaffino & te Kronnie, 1988), avian and mammalian skeletal muscles (Julian, Moss & Waller, 1981;Reiser, Moss, Giulian & Greaser, 1985; Sweeney, Kushmerick, Mabuchi, Gergely & Sreter, 1986; Eddinger Greaser, Sweeney, Kushmerick, Mabuchi, Sreter & Gergely, 1988; Moss, Reiser, Greaser & Eddinger, 1990; Rome, Sosnicki & Goble, 1990). However, there is considerable variation in Vmax in muscle fibres, especially within fast-twitch (type II) fibres, which 596 may be due to the presence of type II MHC subtypes and/or variable ratios of myosin alkali light chains, although experimental evidence is inconsistent on this point (Julian et al 1981;Sweeney et al 1986Sweeney et al , 1988Lannergren, 1987;Greaser et al 1988;Reiser et al 1988;Ruff & Whittlesey, 1991). These inconsistencies may, at least in part, be related to different methods for determining MHC and myosin light chain (MLC) compositions in single muscle fibres or incomplete characterization of MHC or MLC subtypes.…”

Section: Introductionmentioning

confidence: 99%

Maximum velocity of shortening in relation to myosin isoform composition in single fibres from human skeletal muscles.

Larsson

Moss

1993

The Journal of Physiology

459

463

View full text Add to dashboard Cite

SUMMARY1. Maximum velocity of shortening (Vmax) and compositions of myosin heavy chain (MHC) and myosin light chain (MLC) isoforms were determined in single fibres from the soleus or the lateral region of the quadriceps (vastus lateralis) muscles in man. Muscle samples were obtained by percutaneous biopsy, and membranes were permeabilized by glycerol treatment (chemical skinning) or by freeze-drying.2. Types I, IIA and JIB MHCs were resolved from single fibre segments by 6% sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and five different fibre types were identified: fibres containing type I MHC, types I and IIA MHCs, type IIA MHC, types IIA and IIB MHCs, and type IIB MHC. Only a few fibres co-expressed types I and II A MHCs but 28 % of all quadriceps fibres expressed both IIA and IIB MHCs in variable proportions. Fibres co-expressing types I and IIB MHCs were not found.3. Alkali (MLC1 and MLC3) and dithio nitrobenzoic acid (DTNB) (MLC2) myosin light chains were observed in all type II fibres in variable proportions. MLC (MLC1S and MLC2S) isoforms from type I fibres had lower migration rates than the corresponding isoforms from type II fibres (MLC1f and MLC2f). More than half of type I fibres in both soleus (65%) and quadriceps (68%) muscles also expressed 'fast' MLC3 and 36 % of the type II fibres from quadriceps muscle expressed the slow isoform of MLC2.4. Differences were observed in some mechanical characteristics of freeze-dried versus chemically skinned fibres. Maximum tension (PO) and specific tension were lower in freeze-dried types I and II A fibres than in chemically skinned, while no differences were observed in the II A/B fibres. was observed in quadriceps fibres (0-2A41 muscle lengths per second (ML/s)), and a narrower range in the soleus fibres (02-1-0 ML/s). These muscle-specific ranges were related to a homogeneous MHC composition (i.e. type I) in the soleus fibres, while different MHCs (types I, IIA or IIB) and MHC combinations were observed in the quadriceps fibres.6. Vmax was highly dependent on MHC composition and significant differences (P < 0 001) were observed between fibre types. Vmax values in types I, IIA and IIB fibres from quadriceps were 0 3 + 0 1 (n = 32), 1 0 + 0-4 (n = 22) and 3 1 + 0-8 ML/s (n = 7), respectively. Mean Vmax in type I fibres from soleus (0-3 + 0-2 ML/s) were identical to values from quadriceps.7 9. The relative proportions of types I, II A and II B MHCs in human single skeletal muscle fibres appear to be the major determinant of mechanical Vmax. This study also demonstrates that important contractile properties together with myosin isoform composition can be studied in human short fibre segments obtained by percutaneous muscle biopsy.

show abstract

Section: Introductionmentioning

confidence: 99%

Maximum velocity of shortening in relation to myosin isoform composition in single fibres from human skeletal muscles.

Larsson

Moss

1993

The Journal of Physiology

459

463

View full text Add to dashboard Cite

show abstract

“…6–9,11,24,25 The quantity and composition of myofibrillar and soluble proteins vary among these three fiber types. The calcium‐tension relationships of type I, IIa, and IIb fiber contractile proteins differ 24,25 . Myosin heavy chains differ among type I, IIa, and IIb fibers 24 .…”

Section: Introductionmentioning

confidence: 99%

Sodium Channel Regulation of Skeletal Muscle Membrane Excitability^a

Ruff

1997

Annals of the New York Academy of Sciences

Self Cite

View full text Add to dashboard Cite

“…Slow and fast skeletal muscle fibers express type I and type II myosin, respectively, and these myosin isoenzymes have different ATPase activity (2). Previous studies from multiple investigators have demonstrated the contribution of four skeletal muscle myosin heavy chain (MHC) isoforms (types I, IIa, IIx, and IIb) to the magnitude and velocity of contraction of different types of muscle fibers (29,45).…”

mentioning

confidence: 99%

Coupled expression of troponin T and troponin I isoforms in single skeletal muscle fibers correlates with contractility

Brotto

Biesiadecki

Brotto

et al. 2006

American Journal of Physiology-Cell Physiology

View full text Add to dashboard Cite

Striated muscle contraction is powered by actin-activated myosin ATPase. This process is regulated by Ca(2+) via the troponin complex. Slow- and fast-twitch fibers of vertebrate skeletal muscle express type I and type II myosin, respectively, and these myosin isoenzymes confer different ATPase activities, contractile velocities, and force. Skeletal muscle troponin has also diverged into fast and slow isoforms, but their functional significance is not fully understood. To investigate the expression of troponin isoforms in mammalian skeletal muscle and their functional relationship to that of the myosin isoforms, we concomitantly studied myosin, troponin T (TnT), and troponin I (TnI) isoform contents and isometric contractile properties in single fibers of rat skeletal muscle. We characterized a large number of Triton X-100-skinned single fibers from soleus, diaphragm, gastrocnemius, and extensor digitorum longus muscles and selected fibers with combinations of a single myosin isoform and a single class (slow or fast) of the TnT and TnI isoforms to investigate their role in determining contractility. Types IIa, IIx, and IIb myosin fibers produced higher isometric force than that of type I fibers. Despite the polyploidy of adult skeletal muscle fibers, the expression of fast or slow isoforms of TnT and TnI is tightly coupled. Fibers containing slow troponin had higher Ca(2+) sensitivity than that of the fast troponin fibers, whereas fibers containing fast troponin showed a higher cooperativity of Ca(2+) activation than that of the slow troponin fibers. These results demonstrate distinct but coordinated regulation of troponin and myosin isoform expression in skeletal muscle and their contribution to the contractile properties of muscle.

show abstract

Ca‐, Sr‐tension relationships and contraction velocities of human muscle fibers

Cited by 19 publications

References 34 publications

Maximum velocity of shortening in relation to myosin isoform composition in single fibres from human skeletal muscles.

Maximum velocity of shortening in relation to myosin isoform composition in single fibres from human skeletal muscles.

Sodium Channel Regulation of Skeletal Muscle Membrane Excitability^a

Coupled expression of troponin T and troponin I isoforms in single skeletal muscle fibers correlates with contractility

Contact Info

Product

Resources

About

Ca‐, Sr‐tension relationships and contraction velocities of human muscle fibers

Cited by 19 publications

References 34 publications

Maximum velocity of shortening in relation to myosin isoform composition in single fibres from human skeletal muscles.

Maximum velocity of shortening in relation to myosin isoform composition in single fibres from human skeletal muscles.

Sodium Channel Regulation of Skeletal Muscle Membrane Excitabilitya

Coupled expression of troponin T and troponin I isoforms in single skeletal muscle fibers correlates with contractility

Contact Info

Product

Resources

About

Sodium Channel Regulation of Skeletal Muscle Membrane Excitability^a