The remodelling of skeletal muscle for indefatigable hemodynamic work

1991 ◽  
Vol 69 (2) ◽  
pp. 230-237 ◽  
Author(s):  
J. N. K. Odim ◽  
C. Li ◽  
C. Desrosiers ◽  
R. C.-J. Chiu ◽  
P. J. O'Brien ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Pulse Train ◽  
Therapeutic Potential ◽  
Low Frequency ◽  
Myosin Isoforms ◽  
Cardiac Assist ◽  
Cardiac Assist Devices ◽  
Fast Twitch ◽  
Train Stimulation ◽  
Muscle Transformation

Skeletal muscle possesses inherent plasticity of gene expression. Low frequency pulse-train stimulation can remodel the biochemical machinery that confers physiological expression and fatigue resistance approaching that of the myocardium. This fatigue-resistant muscle can generate sufficient force to meet the power requirements for useful cardiac work. This ultimate goal is currently being pursued in models of cardiomyoplasty and muscle-powered cardiac assist devices. In this article, we review the three major subcellular systems subserving canine skeletal muscle transformation and compare them to those of cardiac muscle. The magnitude of the problem of clinical heart failure and the feasibility of fatigue-resistant skeletal muscle joining the therapeutic armamentarium are addressed. The adaptation and transformation of fast-twitch skeletal muscle in response to chronic electrical stimulation augers therapeutic potential as an endogenous, readily available power source for myocardial assistance. The basis mechanisms of skeletal muscle fatigue require elucidation to gain a complete and thorough understanding of how to manipulate this property to provide continuous hemodynamic work.Key words: muscle transformation, pulse-train stimulation, cardiomyoplasty, counterpulsation, cardiac assist, myosin isoforms, sarcoplasmic reticulum ATPase, myofibrillar ATPase.

Skeletal Muscle: A Potential Power Source for Cardiac Assist Devices

Physiology ◽  
1987 ◽  
Vol 2 (6) ◽  
pp. 223-226
Author(s):  
A. Acker M, ◽  
LW Stephenson
Keyword(s):  
Skeletal Muscle ◽  
Heart Disease ◽  
Therapeutic Approach ◽  
Heart Defects ◽  
Power Source ◽  
Assist Devices ◽  
Cardiac Assist ◽  
Cardiac Assist Devices ◽  
End Stage ◽  
Congential Heart Defects

Skeletal muscle has a tremendous capacity for adaptation in increased use, a property that makes in potentially suitable to assist the heart in pumping blood. Heart "ventricles" capable of pumping blood chronically in circulation have been developed based on this concept. Such pumps may some day represent an alternate therapeutic approach to patients with end-stage heart disease or infants with certain congential heart defects.

scholarly journals An analysis of the relationships between subthreshold electrical properties and excitability in skeletal muscle

2011 ◽  
Vol 138 (1) ◽  
pp. 73-93 ◽  
Author(s):  
Thomas H. Pedersen ◽  
Christopher L.-H. Huang ◽  
James A. Fraser
Keyword(s):  
Skeletal Muscle ◽  
Electrical Properties ◽  
Muscle Activity ◽  
Neuromuscular Transmission ◽  
Muscle Fibers ◽  
Low Frequency ◽  
Mammalian Muscle ◽  
Fast Twitch ◽  
T System

Skeletal muscle activation requires action potential (AP) initiation followed by its sarcolemmal propagation and tubular excitation to trigger Ca2+ release and contraction. Recent studies demonstrate that ion channels underlying the resting membrane conductance (GM) of fast-twitch mammalian muscle fibers are highly regulated during muscle activity. Thus, onset of activity reduces GM, whereas prolonged activity can markedly elevate GM. Although these observations implicate GM regulation in control of muscle excitability, classical theoretical studies in un-myelinated axons predict little influence of GM on membrane excitability. However, surface membrane morphologies differ markedly between un-myelinated axons and muscle fibers, predominantly because of the tubular (t)-system of muscle fibers. This study develops a linear circuit model of mammalian muscle fiber and uses this to assess the role of subthreshold electrical properties, including GM changes during muscle activity, for AP initiation, AP propagation, and t-system excitation. Experimental observations of frequency-dependent length constant and membrane-phase properties in fast-twitch rat fibers could only be replicated by models that included t-system luminal resistances. Having quantified these resistances, the resulting models showed enhanced conduction velocity of passive current flow also implicating elevated AP propagation velocity. Furthermore, the resistances filter passive currents such that higher frequency current components would determine sarcolemma AP conduction velocity, whereas lower frequency components excite t-system APs. Because GM modulation affects only the low-frequency membrane impedance, the GM changes in active muscle would predominantly affect neuromuscular transmission and low-frequency t-system excitation while exerting little influence on the high-frequency process of sarcolemmal AP propagation. This physiological role of GM regulation was increased by high Cl− permeability, as in muscle endplate regions, and by increased extracellular [K+], as observed in working muscle. Thus, reduced GM at the onset of exercise would enhance t-system excitation and neuromuscular transmission, whereas elevated GM after sustained activity would inhibit these processes and thereby accentuate muscle fatigue.

Biochemical transformation of canine skeletal muscle for use in cardiac-assist devices

1990 ◽  
Vol 68 (4) ◽  
pp. 1481-1485 ◽  
Author(s):  
C. D. Ianuzzo ◽  
N. Hamilton ◽  
P. J. O'Brien ◽  
C. Desrosiers ◽  
R. Chiu
Keyword(s):  
Skeletal Muscle ◽  
Electrical Stimulation ◽  
Atpase Activity ◽  
Type I ◽  
Canine Heart ◽  
Myofibrillar Atpase ◽  
Assist Devices ◽  
Cardiac Assist ◽  
Myofibrillar Atpase Activity ◽  
Cardiac Assist Devices

Skeletal muscle has an inherent biochemical phenotypic plasticity that provides the possibility for it to be remodeled into a “heart-like” muscle for use in cardiac-assist devices. The purpose of this study was to chronically stimulate skeletal muscle electrically to transform the biochemical capacities of the three major subcellular systems (i.e., metabolic, calcium regulating, and contractile) to resemble those of heart muscle. The latissimus dorsi muscle (LDM) of mongrel dogs weighing 22-27 kg was stimulated via the thoracodorsal nerve at 2 Hz for 6-8 wk. This stimulation protocol reduced the phosphorylase (glycogenolytic) and phosphofructokinase (glycolytic) activities by 70%. The aerobic (citrate synthase activity) and fatty acid oxidative (3-hydroxyacyl-CoA dehydrogenase activity) capacities were not significantly increased by chronic stimulation and remained at about one-fourth those in the canine heart. The calcium-dependent sarcoplasmic reticulum adenosinetriphosphatase (ATPase) activity in the microsomal fraction, which was sixfold greater in the nonstimulated LDM than in the heart, was reduced by electrical stimulation to a level similar to that of the dog heart. The contractile capacity was evaluated by determining the percentage of types I and II fibers, the myofibrillar ATPase activity, and the proportion of myosin isoforms. The transformed muscle was comprised of 93 +/- 2% type I fibers, a myofibrillar ATPase activity similar to that in heart with primarily a slow-twitch muscle myosin isoform. In conclusion, electrical stimulation of canine LDM at 2 Hz for 6-8 wk resulted in two of the three biochemical systems, which confer physiological expression and fatigue resistance to muscle being transformed to resemble those of the myocardium.

Physiologic characteristics of canine skeletal muscle: implications for timing skeletal muscle cardiac assist devices

2001 ◽  
Vol 72 (4) ◽  
pp. 1336-1342
Author(s):  
George V Letsou ◽  
James F Hogan ◽  
Charles C Miller ◽  
John A Elefteriades ◽  
David Francischelli ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Assist Devices ◽  
Cardiac Assist ◽  
Cardiac Assist Devices

Biochemical and Functional Correlates of Myocardium-Like Transformed Skeletal Muscle as a Power Source for Cardiac Assist Devices

1989 ◽  
Vol 4 (2) ◽  
pp. 171-179 ◽  
Author(s):  
RAY C.-J. CHIU ◽  
GARY KOCHAMBA ◽  
GARRETT WALSH ◽  
MICHAEL DEWAR ◽  
CAROLYNE DESROSIERS ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Power Source ◽  
Assist Devices ◽  
Cardiac Assist ◽  
Cardiac Assist Devices

SUSTAINED SKELETAL MUSCLE POWER FOR CARDIAC ASSIST DEVICES

ASAIO Journal ◽  
2000 ◽  
Vol 46 (2) ◽  
pp. 233
Author(s):  
S H Reichenbach ◽  
G D Egrie ◽  
S M Marinache ◽  
K J Gustafson ◽  
D J Farrar ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Muscle Power ◽  
Assist Devices ◽  
Cardiac Assist ◽  
Cardiac Assist Devices

Sustained Skeletal Muscle Power for Cardiac Assist Devices: Implications of Metabolic Constraints

ASAIO Journal ◽  
2001 ◽  
Vol 47 (5) ◽  
pp. 541-547 ◽  
Author(s):  
S. H. Reichenbach ◽  
G. D. Egrie ◽  
S. M. Marinache ◽  
K. J. Gustafson ◽  
D. J. Farrar ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Muscle Power ◽  
Assist Devices ◽  
Cardiac Assist ◽  
Cardiac Assist Devices
Sign in / Sign up

Export Citation Format

Share Document