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Maximum tension and force-velocity properties of fatigued, single Xenopus muscle fibres studied by caffeine and high K+.
Lännergren J, Westerblad H.
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1. The importance of reduced maximum force-generating capacity in the development of skeletal muscle fatigue has been studied using potassium and caffeine contractures as tools. 2. Single, intact fibres isolated from the lumbrical and iliofibularis muscles of Xenopus were fatigued by repeated tetanic stimulations until they produced close to 40% of the original tetanic tension (P0). Using this stimulation scheme three major types of fibres can be distinguished: easily fatigued (type 1), fatigue resistant (type 2), and very fatigue-resistant (type 3) fibres (Westerblad & Lännergren, 1986). 3. When activated by 8-15 mM-caffeine-Ringer solutions fatigued fibres of all three types developed tensions similar to those of controls (81.0 +/- 6.6 vs. 83.9 +/- 4.2% of P0, respectively; means +/- S.D.). 4. Tension output also increased markedly when fatigued fibres were depolarized by 190 mM-K+ solution. The tension produced was in this case fibre type dependent: 71.4 +/- 6.6, 81.3 +/- 2.5 and 95.0 +/- 4.4% of P0 in fibre types 1, 2 and 3, respectively. 5. Force-velocity measurements were performed during caffeine contractures in fatigued iliofibularis fibres (types 1 and 2) to obtain more information about the functional state of cross-bridges. 6. In fatigued type 1 fibres the shortening velocity was reduced to about 25% of that in controls, while it was not significantly depressed in type 2 fibres. 7. It is concluded that cross-bridges of fatigued fibres can produce nearly full tension, but they may work at a much slower rate in this state. 8. Fibre types 1 and 2 mostly display a long-lasting, reversible state of severely depressed tension production during the recovery period, which has been named post-contractile depression, PCD (Westerblad & Lännergren, 1986). Fibres tested in this state generated full caffeine-activated tension and the shortening velocity was not significantly reduced. The tension output during K+ contractures was, however, markedly depressed (12.4 +/- 4.1% of P0). 9. In conclusion, cross-bridges are able to produce close to full tension during PCD as well as in the fatigued state if they are fully activated. The form of functional impairment seems, however, not to be the same in the two cases.
Baylor,
Sarcoplasmic reticulum calcium release in frog skeletal muscle fibres estimated from Arsenazo III calcium transients.
1983, Pubmed
Baylor,
Sarcoplasmic reticulum calcium release in frog skeletal muscle fibres estimated from Arsenazo III calcium transients.
1983,
Pubmed Cooke,
Contraction of glycerinated muscle fibers as a function of the ATP concentration.
1979,
Pubmed Cooke,
The effects of ADP and phosphate on the contraction of muscle fibers.
1985,
Pubmed Cooke,
The inhibition of rabbit skeletal muscle contraction by hydrogen ions and phosphate.
1988,
Pubmed Costantin,
Biphasic potassium contractures in frog muscle fibers.
1971,
Pubmed Dawson,
Mechanical relaxation rate and metabolism studied in fatiguing muscle by phosphorus nuclear magnetic resonance.
1980,
Pubmed Dawson,
Muscular fatigue investigated by phosphorus nuclear magnetic resonance.
1978,
Pubmed Edman,
Effects of fatigue and altered pH on isometric force and velocity of shortening at zero load in frog muscle fibres.
1981,
Pubmed Edwards,
Human muscle function and fatigue.
1981,
Pubmed Edwards,
Metabolic changes associated with the slowing of relaxation in fatigued mouse muscle.
1975,
Pubmed Fabiato,
Effects of pH on the myofilaments and the sarcoplasmic reticulum of skinned cells from cardiace and skeletal muscles.
1978,
Pubmed Ferenczi,
The dependence of force and shortening velocity on substrate concentration in skinned muscle fibres from Rana temporaria.
1984,
Pubmed Grabowski,
The effect of repetitive stimulation at low frequencies upon the electrical and mechanical activity of single muscle fibres.
1972,
Pubmed HUXLEY,
Muscle structure and theories of contraction.
1957,
Pubmed Kanaya,
Properties of caffeine- and potassium-contractures in fatigued frog single twitch muscle fibers.
1983,
Pubmed Lännergren,
The effect of temperature and stimulation scheme on fatigue and recovery in Xenopus muscle fibres.
1988,
Pubmed
,
Xenbase Lännergren,
Contractile properties and myosin isoenzymes of various kinds of Xenopus twitch muscle fibres.
1987,
Pubmed
,
Xenbase Metzger,
Greater hydrogen ion-induced depression of tension and velocity in skinned single fibres of rat fast than slow muscles.
1987,
Pubmed Miledi,
Extracellular ions and excitation-contraction coupling in frog twitch muscle fibres.
1984,
Pubmed Nassar-Gentina,
Fatigue and metabolism of frog muscle fibers during stimulation and in response to caffeine.
1981,
Pubmed Nosek,
It is diprotonated inorganic phosphate that depresses force in skinned skeletal muscle fibers.
1987,
Pubmed Renaud,
Is the change in intracellular pH during fatigue large enough to be the main cause of fatigue?
1986,
Pubmed Schneider,
Voltage dependent charge movement of skeletal muscle: a possible step in excitation-contraction coupling.
1973,
Pubmed Schneider,
Depletion of calcium from the sarcoplasmic reticulum during calcium release in frog skeletal muscle.
1987,
Pubmed Smith,
Sarcoplasmic reticulum contains adenine nucleotide-activated calcium channels.
,
Pubmed Stienen,
Dependency of the force-velocity relationships on Mg ATP in different types of muscle fibers from Xenopus laevis.
1988,
Pubmed
,
Xenbase Weber,
The relationship between caffeine contracture of intact muscle and the effect of caffeine on reticulum.
1968,
Pubmed Westerblad,
Force and membrane potential during and after fatiguing, intermittent tetanic stimulation of single Xenopus muscle fibres.
1986,
Pubmed
,
Xenbase Westerblad,
The relation between force and intracellular pH in fatigued, single Xenopus muscle fibres.
1988,
Pubmed
,
Xenbase