scholarly journals Measuring the acute effect of insulin infusion on ATP turnover rate in human skeletal muscle using phosphorus-31 magnetic resonance saturation transfer spectroscopy

2010 ◽  
Vol 23 (8) ◽  
pp. 952-957 ◽  
Author(s):  
Ee Lin Lim ◽  
Kieren G. Hollingsworth ◽  
Peter E. Thelwall ◽  
Roy Taylor
Keyword(s):  
Skeletal Muscle ◽  
Magnetic Resonance ◽  
Human Skeletal Muscle ◽  
Turnover Rate ◽  
Insulin Infusion ◽  
Acute Effect ◽  
Saturation Transfer ◽  
Resonance Saturation ◽  
Atp Turnover

Regulation of phosphorylase a activity in human skeletal muscle

1990 ◽  
Vol 69 (3) ◽  
pp. 919-923 ◽  
Author(s):  
J. M. Ren ◽  
E. Hultman
Keyword(s):  
Skeletal Muscle ◽  
Muscle Contraction ◽  
Human Skeletal Muscle ◽  
Turnover Rate ◽  
Control Mechanism ◽  
Force Generation ◽  
Contracting Muscle ◽  
Atp Turnover ◽  
Quadriceps Femoris Muscles ◽  
Glycogen Breakdown

The control mechanism of glycogenolysis by phosphorylase a in contracting muscle has been investigated. The quadriceps femoris muscles of six subjects were intermittently stimulated at 15 and 50 Hz. The stimulation lasted 9.6 s and was performed twice at 15 Hz and once at 50 Hz. Epinephrine was infused continuously during the experiment. The force generation and ATP turnover rate were nearly twofold higher at 50 Hz than at 15 Hz. Calculated mean Pi was 5.7 and 10.0 mM during the two 15-Hz stimulations and 8.1 mM during the 50-Hz stimulation. Phosphorylase a varied between 85.5 and 91.5% without significant differences between periods. However, the rate of glycogenolysis was twofold higher during the stimulation at 50 Hz than it was at 15 Hz (P less than 0.05) and was related to the ATP turnover rate (r = 0.992). These results demonstrate that rapid glycogen breakdown during muscle contraction cannot be solely explained by transformation of phosphorylase b to a and increased Pi concentration. The contraction intensity may determine the glycogenolytic rate through a transient increase in free AMP level related to the ATP turnover rate.

Effect of insulin on GLUT4 cell surface content and turnover rate in human skeletal muscle as measured by the exofacial bis-mannose photolabeling technique

Diabetes ◽  
1997 ◽  
Vol 46 (12) ◽  
pp. 1965-1969 ◽  
Author(s):  
S. Lund ◽  
G. D. Holman ◽  
J. R. Zierath ◽  
J. Rincon ◽  
L. A. Nolte ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Cell Surface ◽  
Human Skeletal Muscle ◽  
Turnover Rate ◽  
Surface Content

scholarly journals Insulin does not stimulate β-alanine transport into human skeletal muscle

2020 ◽  
Vol 318 (4) ◽  
pp. C777-C786
Author(s):  
Lívia de Souza Gonçalves ◽  
Caroline Kratz ◽  
Lívia Santos ◽  
Victor Henrique Carvalho ◽  
Lucas Peixoto Sales ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Plasma Insulin ◽  
Human Skeletal Muscle ◽  
Insulin Infusion ◽  
Muscle Cells ◽  
Muscle Carnosine ◽  
Blood Samples ◽  
Alanine Transport ◽  
Substrate Concentrations ◽  
Infusion Protocol

To test whether high circulating insulin concentrations influence the transport of β-alanine into skeletal muscle at either saturating or subsaturating β-alanine concentrations, we conducted two experiments whereby β-alanine and insulin concentrations were controlled. In experiment 1, 12 men received supraphysiological amounts of β-alanine intravenously (0.11 g·kg−1·min−1 for 150 min), with or without insulin infusion. β-Alanine and carnosine were measured in muscle before and 30 min after infusion. Blood samples were taken throughout the infusion protocol for plasma insulin and β-alanine analyses. β-Alanine content in 24-h urine was assessed. In experiment 2, six men ingested typical doses of β-alanine (10 mg/kg) before insulin infusion or no infusion. β-Alanine was assessed in muscle before and 120 min following ingestion. In experiment 1, no differences between conditions were shown for plasma β-alanine, muscle β-alanine, muscle carnosine and urinary β-alanine concentrations (all P > 0.05). In experiment 2, no differences between conditions were shown for plasma β-alanine or muscle β-alanine concentrations (all P > 0.05). Hyperinsulinemia did not increase β-alanine uptake by skeletal muscle cells, neither when substrate concentrations exceed the Vmax of β-alanine transporter TauT nor when it was below saturation. These results suggest that increasing insulin concentration is not necessary to maximize β-alanine transport into muscle following β-alanine intake.

Interrelationship of oxidative metabolism and local perfusion demonstrated by NMR in human skeletal muscle

1996 ◽  
Vol 81 (5) ◽  
pp. 2221-2228 ◽  
Author(s):  
Jean-François Toussaint ◽  
Kenneth K. Kwong ◽  
Fidelis M’Kparu ◽  
Robert M. Weisskoff ◽  
Paul J. Laraia ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Magnetic Resonance ◽  
Time Constant ◽  
Oxidative Metabolism ◽  
Human Skeletal Muscle ◽  
Plantar Flexion ◽  
High Energy ◽  
Resonance Spectroscopy ◽  
Mean Flow ◽  
Normal Volunteers

Toussaint, Jean-François, Kenneth K. Kwong, Fidelis M’Kparu, Robert M. Weisskoff, Paul J. LaRaia, and Howard L. Kantor.Interrelationship of oxidative metabolism and local perfusion demonstrated by NMR in human skeletal muscle. J. Appl. Physiol. 81(5): 2221–2228, 1996.—Using nuclear magnetic resonance (NMR), we have examined the relationship of high-energy phosphate metabolism and perfusion in human soleus and gastrocnemius muscles. With31P-NMR spectroscopy, we monitored phosphocreatine (PCr) decay and recovery in eight normal volunteers and four heart failure patients performing ischemic plantar flexion. By using echo-planar imaging, perfusion was independently measured by a local [inversion-recovery (T1-flow)] and a regional technique (NMR-plethysmography). After correction for its pH dependence, PCr recovery time constant is 27.5 ± 8.0 s in normal volunteers, with mean flow 118 ± 75 (soleus and gastrocnemius T1-flow) and 30.2 ± 9.7 ml ⋅ 100 ml−1 ⋅ min−1(NMR-plethysmography-flow). We demonstrate a positive correlation between PCr time constant and local perfusion given by y = 50 − 0.15 x( r 2 = 0.68, P = 0.01) for the 8 normal subjects, and y = 64 − 0.24 x( r 2 = 0.83, P = 0.0001) for the 12 subjects recruited in the study. Regional perfusion techniques also show a significant but weaker correlation. Using this totally noninvasive method, we conclude that aerobic ATP resynthesis is related to the magnitude of perfusion, i.e., O2availability, and demonstrate that magnetic resonance imaging and magnetic resonance spectroscopy together can accurately assess muscle functional status.

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