THE REACTION OF PIGS TO HALOTHANE; CHANGES IN HIGH ENERGY PHOSPHATES AND GLYCOLYTIC INTERMEDIARIES IN SKELETAL MUSCLE

1980 ◽  
Vol 9 (1) ◽  
pp. 131-139
Author(s):  
C.P. Ahern ◽  
P. Wilson ◽  
J.V. McLouqhlin
Keyword(s):  
Skeletal Muscle ◽  
High Energy ◽  
High Energy Phosphates

Anaerobic energy provision in aged skeletal muscle during tetanic stimulation

1991 ◽  
Vol 70 (4) ◽  
pp. 1787-1795 ◽  
Author(s):  
C. B. Campbell ◽  
D. R. Marsh ◽  
L. L. Spriet
Keyword(s):  
Skeletal Muscle ◽  
Energy Demand ◽  
Energy Charge ◽  
High Energy ◽  
High Energy Phosphates ◽  
Fischer 344 ◽  
Charge Potential ◽  
Anaerobic Energy ◽  
Gastrocnemius Muscles

The effect of age on skeletal muscle anaerobic energy metabolism was investigated in adult (11 mo) and aged (25 mo) Fischer 344 rats. Hindlimb skeletal muscles innervated by the sciatic nerve were stimulated to contract with trains of supramaximal impulses (100 ms, 80 Hz) at a train rate of 1 Hz for 60 s, with an occluded circulation. Soleus, plantaris, and red and white gastrocnemius (WG) were sampled from control and stimulated limbs. All muscle masses were reduced with age (9-13%). Peak isometric tensions, normalized per gram of wet muscle, were lower throughout the stimulation in the aged animals (28%). The potential for anaerobic ATP provision was unaltered with age in all muscles, because resting high-energy phosphates and glycogen contents were similar to adult values. Anaerobic ATP provision during stimulation was unaltered by aging in soleus, plantaris, and red gastrocnemius muscles. In the WG, containing mainly fast glycolytic (FG) fibers, ATP and phosphocreatine contents were depleted less in aged muscle. In situ glycogenolysis and glycolysis were 90.0 +/- 4.8 and 69.3 +/- 2.6 mumol/g dry muscle (dm) in adult WG and reduced to 62.3 +/- 6.9 and 51.5 +/- 5.5 mumol/g dm, respectively, in aged WG. Consequently, total anaerobic ATP provision was lower in aged WG (224.5 +/- 20.9 mumol/g dm) vs. adult (292.6 +/- 7.6 mumol/g dm) WG muscle. In summary, the decreased tetanic tension production in aged animals was associated with a decreased anaerobic energy production in FG fibers. Reduced high-energy phosphate use and a greater energy charge potential after stimulation suggested that the energy demand was reduced in aged FG fibers.(ABSTRACT TRUNCATED AT 250 WORDS)

Contractile and metabolic effects of increased creatine kinase activity in mouse skeletal muscle

1996 ◽  
Vol 270 (4) ◽  
pp. C1236-C1245 ◽  
Author(s):  
B. B. Roman ◽  
J. M. Foley ◽  
R. A. Meyer ◽  
A. P. Koretsky
Keyword(s):  
Skeletal Muscle ◽  
Creatine Kinase ◽  
Kinase Activity ◽  
Contractile Function ◽  
Contractile Activity ◽  
High Energy ◽  
Metabolic Effects ◽  
High Energy Phosphates ◽  
Lactate Dehydrogenase Activity ◽  
B Subunit

The effects of increased expression of creatine kinase (CK) in skeletal muscle were studied in control and transgenic animals homozygous for expression of the B subunit of CK. CK activity was 47% higher in transgenic gastrocnemius muscle. The CK activity was distributed as follows: 45 +/- 1% MM dinner, 31 +/- 4% MB dimer, and 22 +/- 5% BB dimer. No significant differences in metabolic or contractile proteins were detected except for a 22% decrease in lactate dehydrogenase activity and a 9% decrease in adenylate kinase activity. The only significant effect in contractile activity was that the rise time of a 5-s isometric contraction was 28% faster in the transgenic muscle. 31P nuclear magnetic resonance (NMR) spectra were obtained from control and transgenic muscles during mechanical activation, and there were no NMR measurable differences detected. These results indicate that a 50% increase in CK activity due to expression of the B subunit does not have large effects on skeletal muscle metabolism or contractile function. Therefore, control muscle has sufficient CK activity to keep up with changes in cellular high-energy phosphates except during the early phase of intense contractile activity.

scholarly journals Redox state and lactate accumulation in human skeletal muscle during dynamic exercise

1987 ◽  
Vol 245 (2) ◽  
pp. 551-556 ◽  
Author(s):  
K Sahlin ◽  
A Katz ◽  
J Henriksson
Keyword(s):  
Skeletal Muscle ◽  
Human Skeletal Muscle ◽  
Redox State ◽  
Lactate Production ◽  
High Energy ◽  
High Energy Phosphates ◽  
Vo2 Max ◽  
Muscle Lactate ◽  
Lactate Accumulation ◽  
Pyruvate Ratio

The relationship between the redox state and lactate accumulation in contracting human skeletal muscle was investigated. Ten men performed bicycle exercise for 10 min at 40 and 75% of maximal oxygen uptake [VO2(max.)], and to fatigue (4.8 +/- 0.6 min; mean +/- S.E.M.) at 100% VO2(max.). Biopsies from the quadriceps femoris muscle were analysed for NADH, high-energy phosphates and glycolytic intermediates. Muscle NADH was 0.20 +/- 0.02 mmol/kg dry wt. of muscle at rest, and decreased to 0.12 +/- 0.01 (P less than 0.01) after exercise at 40% VO2(max.), but no change occurred in the [lactate]/[pyruvate] ratio. These data, together with previous results on isolated cyanide-poisoned soleus muscle, where NADH increased while [lactate]/[pyruvate] ratio was unchanged [Sahlin & Katz (1986) Biochem. J. 239, 245-248], suggest that the observed changes in muscle NADH occurred within the mitochondria. After exercise at 75 and 100% VO2(max.), muscle NADH increased above the value at rest to 0.27 +/- 0.03 (P less than 0.05) and 0.32 +/- 0.04 (P less than 0.001) mmol/kg respectively. Muscle lactate was unchanged after exercise at 40% VO2(max.), but increased substantially at the higher work loads. At 40% VO2(max.), phosphocreatine decreased by 11% compared with the values at rest, and decreased further at the higher work loads. The decrease in phosphocreatine reflects increased ADP and Pi. It is concluded that muscle NADH decreases during low-intensity exercise, but increases above the value at rest during high-intensity exercise. The increase in muscle NADH is consistent with the hypothesis that the accelerated lactate production during submaximal exercise is due to a limited availability of O2 in the contracting muscle. It is suggested that the increases in NADH, ADP and Pi are metabolic adaptations, which primarily serve to activate the aerobic ATP production, and that the increased anaerobic energy production (phosphocreatine breakdown and lactate formation) is a consequence of these changes.

Contraction Failure of Skeletal Muscle of Rats Recovering from Critical Illness

1997 ◽  
Vol 92 (2) ◽  
pp. 189-195 ◽  
Author(s):  
Olav E. Rooyackers ◽  
Matthijs K. C. Hesselink ◽  
Anton J. M. Wagenmakers
Keyword(s):  
Skeletal Muscle ◽  
Critical Illness ◽  
Muscle Tension ◽  
High Energy ◽  
High Energy Phosphates ◽  
Maximal Aerobic Capacity ◽  
Tension Development ◽  
Atp Production ◽  
Stimulation Period ◽  
Subsequent Loss

1. Most patients recovering from critical illness experience enhanced fatiguability. Previously we have shown that zymosan-induced critical illness in rats is attended by a decreased mitochondrial content (maximal aerobic capacity) in skeletal muscle. We investigated whether this decrease results in an increased reduction in high-energy phosphates and a subsequent loss of contractility during in situ electrical stimulation in rats recovering from zymosan treatment. 2. Plantar-flexor muscles of the hindlimb were electrically stimulated via the innervating nerve to develop maximal isometric tetanic contraction. 3. Decreased concentrations of ATP were measured in gastrocnemius muscle of zymosan-treated rats, both at rest and after stimulation, in comparison with ad libitum-fed and pair-fed control rats. However, no differences in the stimulation-induced decreases in high-energy phosphate levels and changes in other metabolites, except ADP, were observed between the groups. Tension development in the zymosan-treated rats was, however, about 85% less compared with the pair-fed controls during the whole stimulation period. 4. We conclude that the primary cause of the loss of muscle tension in zymosan-treated rats is an insensitivity of skeletal muscle to stimulation via the nerve. An additional derangement in ATP production is, however, indicated by the comparable decreases in energy substrates during development of a dramatically lower tension.

scholarly journals Efficiency of human skeletal muscle in vivo: comparison of isometric, concentric, and eccentric muscle action

1997 ◽  
Vol 83 (3) ◽  
pp. 867-874 ◽  
Author(s):  
T. W. Ryschon ◽  
M. D. Fowler ◽  
R. E. Wysong ◽  
A.-R. Anthony ◽  
R. S. Balaban
Keyword(s):  
Skeletal Muscle ◽  
Steady State ◽  
Production Rate ◽  
Human Skeletal Muscle ◽  
Atp Synthesis ◽  
High Energy ◽  
High Energy Phosphates ◽  
Muscle Action ◽  
Atp Production

Ryschon, T. W., Fowler, R. E. Wysong, A.-R. Anthony, and R. S. Balaban. Efficiency of human skeletal muscle in vivo: comparison of isometric, concentric, and eccentric muscle action. J. Appl. Physiol. 83(3): 867–874, 1997.—The purpose of this study was to estimate the efficiency of ATP utilization for concentric, eccentric, and isometric muscle action in the human tibialis anterior and extensor digitorum longus in vivo. A dynamometer was used to quantitate muscle work, or tension, while simultaneous 31P-nuclear magnetic resonance data were collected to monitor ATP, phosphocreatine, inorganic phosphate, and pH. The relative efficiency of the actions was estimated in two ways: steady-state effects on high-energy phosphates and a direct comparison of ATP synthesis rates with work. In the steady state, the cytosolic free energy dropped to the lowest value with concentric activity, followed by eccentric and isometric action for comparative muscle tensions. Estimates of ATP synthesis rates revealed a mechanochemical efficiency [i.e., ATP production rate/work (both in J/s)] of 15.0 ± 1.3% in concentric and 34.7 ± 6.1% in eccentric activity. The estimated maximum ATP production rate was highest in concentric action, suggesting an activation of energy metabolism under these conditions. By using direct measures of metabolic strain and ATP turnover, these data demonstrate a decreasing metabolic efficiency in human muscle action from isometric, to eccentric, to concentric action.

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