Biomaterial Database

Four aspects of creep phenomena in striated muscle. 1991

R P Saldana, and D A Smith

Department of Physics, Monash University, Clayton, Australia.

Four aspects of the slow creep of tension and sarcomere lengths observed during fixed-end tetani are studied with computer simulations, using the instantaneous steady-state (adiabatic) approximation. (1) Most aspects of fixed-end creep phenomena can be simulated in the presence of the passive forces which correctly produce initially shortened end sarcomeres. However, the very large maximum tensions observed with fibres of low resting force for sarcomere lengths greater than 3.0 microns cannot be simulated within the adiabatic approximation. (2) Random variations in the passive tension-length curve between different sarcomeres can predict the reported incidence of contracting sarcomeres in the middle of the fibre, while avoiding significant tension creep when a central segment is length-clamped. They can also reverse the velocity of these sarcomeres during creep in fibres with high resting tension, as observed by Altringham and Bottinelli (1985). At sarcomere lengths of greater than or equal to 3.4 microns we find that spatial variations in passive tension strength also contribute to tension creep. (3) Crossbridge fluctuations in active tension have been estimated from the sliding-filament model, and do not contribute significantly to tension creep. (4) The need for inter-sarcomere stiffness or other mechanisms to produce an additional slow rise in tension at long times, and to smooth the sarcomere length distribution, is assessed.

UI	MeSH Term	Description	Entries
D008962	Models, Theoretical	Theoretical representations that simulate the behavior or activity of systems, processes, or phenomena. They include the use of mathematical equations, computers, and other electronic equipment.	Experimental Model,Experimental Models,Mathematical Model,Model, Experimental,Models (Theoretical),Models, Experimental,Models, Theoretic,Theoretical Study,Mathematical Models,Model (Theoretical),Model, Mathematical,Model, Theoretical,Models, Mathematical,Studies, Theoretical,Study, Theoretical,Theoretical Model,Theoretical Models,Theoretical Studies
D009119	Muscle Contraction	A process leading to shortening and/or development of tension in muscle tissue. Muscle contraction occurs by a sliding filament mechanism whereby actin filaments slide inward among the myosin filaments.	Inotropism,Muscular Contraction,Contraction, Muscle,Contraction, Muscular,Contractions, Muscle,Contractions, Muscular,Inotropisms,Muscle Contractions,Muscular Contractions
D009132	Muscles	Contractile tissue that produces movement in animals.	Muscle Tissue,Muscle,Muscle Tissues,Tissue, Muscle,Tissues, Muscle
D003198	Computer Simulation	Computer-based representation of physical systems and phenomena such as chemical processes.	Computational Modeling,Computational Modelling,Computer Models,In silico Modeling,In silico Models,In silico Simulation,Models, Computer,Computerized Models,Computer Model,Computer Simulations,Computerized Model,In silico Model,Model, Computer,Model, Computerized,Model, In silico,Modeling, Computational,Modeling, In silico,Modelling, Computational,Simulation, Computer,Simulation, In silico,Simulations, Computer
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012518	Sarcomeres	The repeating contractile units of the MYOFIBRIL, delimited by Z bands along its length.	Sarcomere
D013746	Tetany	A disorder characterized by muscle twitches, cramps, and carpopedal spasm, and when severe, laryngospasm and seizures. This condition is associated with unstable depolarization of axonal membranes, primarily in the peripheral nervous system. Tetany usually results from HYPOCALCEMIA or reduced serum levels of MAGNESIUM that may be associated with HYPERVENTILATION; HYPOPARATHYROIDISM; RICKETS; UREMIA; or other conditions. (From Adams et al., Principles of Neurology, 6th ed, p1490)	Spasmophilia,Tetany, Neonatal,Tetanilla,Neonatal Tetanies,Neonatal Tetany,Spasmophilias,Tetanies,Tetanies, Neonatal,Tetanillas