A rapid algorithm for processing digital physiologic signals: Application to skeletal muscle contractions

2006 ◽  
Vol 1 (4) ◽  
pp. 307-313 ◽  
Author(s):  
Roop C. Jayaraman ◽  
Matthew T. Latourette ◽  
James E. Siebert ◽  
Robert W. Wiseman
Keyword(s):  
Skeletal Muscle ◽  
Muscle Contractions

AMP-activated protein kinase activity and glucose uptake in rat skeletal muscle

2001 ◽  
Vol 280 (5) ◽  
pp. E677-E684 ◽  
Author(s):  
Nicolas Musi ◽  
Tatsuya Hayashi ◽  
Nobuharu Fujii ◽  
Michael F. Hirshman ◽  
Lee A. Witters ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Protein Kinase ◽  
Glucose Uptake ◽  
Muscle Contractions ◽  
Treadmill Running ◽  
Dependent Manner ◽  
Rat Skeletal Muscle ◽  
Amp Activated Protein Kinase ◽  
Dose Dependent

The AMP-activated protein kinase (AMPK) has been hypothesized to mediate contraction and 5-aminoimidazole-4-carboxamide 1-β-d-ribonucleoside (AICAR)-induced increases in glucose uptake in skeletal muscle. The purpose of the current study was to determine whether treadmill exercise and isolated muscle contractions in rat skeletal muscle increase the activity of the AMPKα1 and AMPKα2 catalytic subunits in a dose-dependent manner and to evaluate the effects of the putative AMPK inhibitors adenine 9-β-d-arabinofuranoside (ara-A), 8-bromo-AMP, and iodotubercidin on AMPK activity and 3- O-methyl-d-glucose (3-MG) uptake. There were dose-dependent increases in AMPKα2 activity and 3-MG uptake in rat epitrochlearis muscles with treadmill running exercise but no effect of exercise on AMPKα1 activity. Tetanic contractions of isolated epitrochlearis muscles in vitro significantly increased the activity of both AMPK isoforms in a dose-dependent manner and at a similar rate compared with increases in 3-MG uptake. In isolated muscles, the putative AMPK inhibitors ara-A, 8-bromo-AMP, and iodotubercidin fully inhibited AICAR-stimulated AMPKα2 activity and 3-MG uptake but had little effect on AMPKα1 activity. In contrast, these compounds had absent or minimal effects on contraction-stimulated AMPKα1 and -α2 activity and 3-MG uptake. Although the AMPKα1 and -α2 isoforms are activated during tetanic muscle contractions in vitro, in fast-glycolytic fibers, the activation of AMPKα2-containing complexes may be more important in regulating exercise-mediated skeletal muscle metabolism in vivo. Development of new compounds will be required to study contraction regulation of AMPK by pharmacological inhibition.

Output of skeletal muscle contractions A study of isokinetic plantar flexion in athletes

1982 ◽  
Vol 115 (2) ◽  
pp. 193-199 ◽  
Author(s):  
AXEL R. FUGL-MEYER ◽  
KJELL H. MILD ◽  
JAN HÖRNSTEN
Keyword(s):  
Skeletal Muscle ◽  
Plantar Flexion ◽  
Muscle Contractions

Perivascular and tissue PO2 in contracting rat spinotrapezius muscle

1987 ◽  
Vol 252 (6) ◽  
pp. H1192-H1202 ◽  
Author(s):  
J. M. Lash ◽  
H. G. Bohlen
Keyword(s):  
Skeletal Muscle ◽  
Muscle Contractions ◽  
Large Decrease ◽  
Functional Hyperemia ◽  
Biochemical Status ◽  
Tissue Po2 ◽  
Close Proximity ◽  
Exercise Hyperemia ◽  
Capillary Bed

This study evaluated the possibility that during skeletal muscle contractions tissue O2 tension (Po2) around arterioles and venules decreases substantially more than in the middle of the capillary bed and thereby influences functional hyperemia. Periarteriolar [H+] and [K+] were also measured because most large arterioles are in close proximity to venules such that the biochemical status of the periarteriolar tissue could be influenced by a large decrease in O2 availability in the annulet of tissue surrounding the venules. Stimulation frequencies in the range of 2-12 Hz were used to activate the rat spinotrapezius muscle. Periarteriolar and capillary bed Po2, [H+], and [K+] changed during the first few minutes of stimulation but were restored to near resting concentrations as the functional hyperemia developed. However, perivenular Po2 decreased rapidly to approximately 50-60% of the resting gas tension as contractions began, and only minor recovery occurred. Elevation of tissue and periarteriolar Po2 with an O2-enriched superfusion solution did not prevent dilation during contractions to the same diameter as during the response at very low superfusion Po2. Therefore, the extent to which O2 influences arteriolar dilation and exercise hyperemia in the spinotrapezius muscle of the rat may depend less on periarteriolar and capillary bed Po2 than on the release of vasoactive materials from the nearby perivenular tissues as the availability of O2 decreases.

A malonyl-CoA fuel-sensing mechanism in muscle: effects of insulin, glucose, and denervation

1995 ◽  
Vol 269 (2) ◽  
pp. E283-E289 ◽  
Author(s):  
A. K. Saha ◽  
T. G. Kurowski ◽  
N. B. Ruderman
Keyword(s):  
Skeletal Muscle ◽  
Plasma Insulin ◽  
Contractile Activity ◽  
High Plasma ◽  
Muscle Contractions ◽  
Glucose Levels ◽  
Malonyl Coa ◽  
Ad Libitum ◽  
Sciatic Nerve Stimulation

Increases in the concentration of malonyl-CoA in skeletal muscle have been observed in the KKAy mouse, an obese rodent with high plasma insulin and glucose levels [Saha et al. Am. J. Physiol. 267 (Endocrinol. Metab. 30): E95-E101, 1994]. To assess whether insulin and glucose directly regulate malonyl-CoA in muscle, soleus muscles from young rats were incubated with insulin and glucose at various concentrations, and their content of malonyl-CoA was determined. In addition, the effect on malonyl-CoA of denervation and electrically induced muscle contractions was assessed. The concentration of malonyl-CoA in the soleus, taken directly from a rat fed ad libitum, was 2.0 +/- 0.2 nmol/g. In muscles incubated for 20 min in a medium devoid of added insulin and glucose, the concentration was decreased to 0.8 +/- 0.2 nmol/g. When the medium contained 0.5, 7.5, or 30 mM glucose, malonyl-CoA levels were 1.3 +/- 0.1, 1.8 +/- 0.1, or 2.4 +/- 0.2 nmol/g, respectively, in the absence of insulin and 1.7 +/- 0.1, 4.6 +/- 0.3, or 5.5 +/- 0.6 nmol/g in its presence (10 mU/ml). Compared with its level in a control muscle, the concentration of malonyl-CoA was increased threefold in the soleus 6-8 h after denervation and remained twofold higher for > or = 48 h. In contrast, muscle contractions induced by sciatic nerve stimulation, in vivo, acutely decreased the concentration of malonyl-CoA by 30-35%. The results indicate that insulin and glucose, and probably contractile activity, regulate the concentration of malonyl-CoA in muscle.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals The effect of repeated bouts of electrical stimulation‐induced muscle contractions on proteolytic signaling in rat skeletal muscle

2021 ◽  
Vol 9 (9) ◽  
Author(s):  
Takaya Kotani ◽  
Junya Takegaki ◽  
Yuki Tamura ◽  
Karina Kouzaki ◽  
Koichi Nakazato ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Electrical Stimulation ◽  
Muscle Contractions ◽  
Rat Skeletal Muscle

scholarly journals Classical and adaptive control of ex vivo skeletal muscle contractions using Functional Electrical Stimulation (FES)

PLoS ONE ◽  
2017 ◽  
Vol 12 (3) ◽  
pp. e0172761
Author(s):  
Paola Jaramillo Cienfuegos ◽  
Adam Shoemaker ◽  
Robert W. Grange ◽  
Nicole Abaid ◽  
Alexander Leonessa
Keyword(s):  
Skeletal Muscle ◽  
Adaptive Control ◽  
Electrical Stimulation ◽  
Functional Electrical Stimulation ◽  
Ex Vivo ◽  
Muscle Contractions

Effects of contraction on localization of GLUT4 and v-SNARE isoforms in rat skeletal muscle

2009 ◽  
Vol 297 (5) ◽  
pp. R1228-R1237 ◽  
Author(s):  
Adam J. Rose ◽  
Jacob Jeppesen ◽  
Bente Kiens ◽  
Erik A. Richter
Keyword(s):  
Skeletal Muscle ◽  
Membrane Vesicle ◽  
Surface Membrane ◽  
Muscle Contractions ◽  
Low Density ◽  
Increase Glucose Uptake ◽  
Intracellular Storage ◽  
Resting Muscle ◽  
Contralateral Muscle

In skeletal muscle, contractions increase glucose uptake due to a translocation of GLUT4 glucose transporters from intracellular storage sites to the surface membrane. Vesicle-associated membrane proteins (VAMPs) are believed to play an important role in docking and fusion of the GLUT4 transporters at the surface membrane. However, knowledge about which VAMP isoforms colocalize with GLUT4 vesicles in mature skeletal muscle and whether they translocate during muscle contractions is incomplete. The aim of the present study was to further identify VAMP isoforms, which are associated with GLUT4 vesicles and examine which VAMP isoforms translocate to surface membranes in skeletal muscles undergoing contractions. VAMP2, VAMP3, VAMP5, and VAMP7 were enriched in immunoprecipitated GLUT4 vesicles. In response to 20 min of in situ contractions, there was a redistribution of GLUT4 (+64 ± 13%), transferrin receptor (TfR; +75 ± 22%), and insulin-regulated aminopeptidase (IRAP; +70 ± 13%) to fractions enriched in heavy membranes away from low-density membranes (−32 ± 7%; −18 ± 12%; −33 ± 9%; respectively), when compared with the resting contralateral muscle. Similarly, there was a redistribution of VAMP2 (+240 ± 40%), VAMP5 (+79 ± 9%), and VAMP7 (+79 ± 29%), but not VAMP3, to fractions enriched in heavy membranes away from low-density membranes (−49 ± 10%, −54 ± 9%, −14 ± 11%, respectively) in contracted vs. resting muscle. In summary, VAMP2, VAMP3, VAMP5, and VAMP7 coimmunoprecipitate with intracellular GLUT4 vesicles in muscle, and VAMP2, VAMP5, VAMP7, but not VAMP3, translocate to the cell surface membranes similar to GLUT4, TfR, and IRAP in response to muscle contractions. These findings suggest that VAMP2, VAMP5, and VAMP7 may be involved in translocation of GLUT4 during muscle contractions.

scholarly journals Ultrasound Measurement of Skeletal Muscle Contractile Parameters Using Flexible and Wearable Single-Element Ultrasonic Sensor

Sensors ◽  
2020 ◽  
Vol 20 (13) ◽  
pp. 3616 ◽  
Author(s):  
Ibrahim AlMohimeed ◽  
Yuu Ono
Keyword(s):  
Skeletal Muscle ◽  
Polyvinylidene Fluoride ◽  
Ultrasonic Method ◽  
Muscle Contractions ◽  
Ultrasonic Sensor ◽  
Ultrasound Measurement ◽  
Single Element ◽  
Tissue Thickness ◽  
Contractile Parameters ◽  
Muscle Contractile

Skeletal muscle is considered as a near-constant volume system, and the contractions of the muscle are related to the changes in tissue thickness. Assessment of the skeletal muscle contractile parameters such as maximum contraction thickness ( T h ), contraction time ( T c ), contraction velocity ( V c ), sustain time ( T s ), and half-relaxation ( T r ) provides valuable information for various medical applications. This paper presents a single-element wearable ultrasonic sensor (WUS) and a method to measure the skeletal muscle contractile parameters in A-mode ultrasonic data acquisition. The developed WUS was made of double-layer polyvinylidene fluoride (PVDF) piezoelectric polymer films with a simple and low-cost fabrication process. A flexible, lightweight, thin, and small size WUS would provide a secure attachment to the skin surface without affecting the muscle contraction dynamics of interest. The developed WUS was employed to monitor the contractions of gastrocnemius (GC) muscle of a human subject. The GC muscle contractions were evoked by the electrical muscle stimulation (EMS) at varying EMS frequencies from 2 Hz up to 30 Hz. The tissue thickness changes due to the muscle contractions were measured by utilizing a time-of-flight method in the ultrasonic through-transmission mode. The developed WUS demonstrated the capability to monitor the tissue thickness changes during the unfused and fused tetanic contractions. The tetanic progression level was quantitatively assessed using the parameter of the fusion index (FI) obtained. In addition, the contractile parameters ( T h , T c , V c , T s , and T r ) were successfully extracted from the measured tissue thickness changes. In addition, the unfused and fused tetanus frequencies were estimated from the obtained FI-EMS frequency curve. The WUS and ultrasonic method proposed in this study could be a valuable tool for inexpensive, non-invasive, and continuous monitoring of the skeletal muscle contractile properties.

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