Biomaterial Database

Functional development of engineered skeletal muscle from adult and neonatal rats. 2001

P E Kosnik, and J A Faulkner, and R G Dennis

Department of Biomedical Engineering and Institute of Gerontology, University of Michigan, Ann Arbor, Michigan 48109-2007, USA.

A myooid is a three-dimensional skeletal muscle construct cultured from mammalian myoblasts and fibroblasts. The purpose was to compare over several weeks in culture the morphology, excitability, and contractility of myooids developed from neonatal and adult rat cells. The hypotheses tested were as follows: (1) baseline forces of myooids correlate with the cross-sectional area (CSA) of the myooids composed of fibroblasts, and (2) peak isometric tetanic forces normalized by total CSA (specific P(o)) of neonatal and adult rat myooids are not different. Electrical field stimulation was used to measure the excitability and peak tetanic forces. The proportion of the CSA composed of fibroblasts was greater for neonatal (40%) than adult (17%) myooids. For all myooids the baseline passive force normalized by fibroblast CSA (mean = 5.5 kPa) correlated with the fibroblast CSA (r(2) = 0.74). A two-element cylindrical model was analyzed to determine the contributions of fibroblasts and myotubes to the baseline force. At each measurement period, the specific P(o) of the adult myooids was greater than that of the neonatal myooids. The specific P(o) of the adult myooids was approximately 1% of the control value for adult muscles and did not change with time in culture, while that of neonatal myooids increased.

UI	MeSH Term	Description	Entries
D007537	Isometric Contraction	Muscular contractions characterized by increase in tension without change in length.	Contraction, Isometric,Contractions, Isometric,Isometric Contractions
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
D002907	Chronaxy	The shortest duration of an electrical stimulus where the threshold amplitude is twice the rheobase - the minimum required for eliciting an ACTION POTENTIAL at any time period. It is a measure of the excitability of nerve or muscle tissue, and is characteristic of types and/or condition of the nerve or muscle cells in the tissue.	Chronaxie
D004558	Electric Stimulation	Use of electric potential or currents to elicit biological responses.	Stimulation, Electric,Electrical Stimulation,Electric Stimulations,Electrical Stimulations,Stimulation, Electrical,Stimulations, Electric,Stimulations, Electrical
D005347	Fibroblasts	Connective tissue cells which secrete an extracellular matrix rich in collagen and other macromolecules.	Fibroblast
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
D000831	Animals, Newborn	Refers to animals in the period of time just after birth.	Animals, Neonatal,Animal, Neonatal,Animal, Newborn,Neonatal Animal,Neonatal Animals,Newborn Animal,Newborn Animals
D013314	Stress, Mechanical	A purely physical condition which exists within any material because of strain or deformation by external forces or by non-uniform thermal expansion; expressed quantitatively in units of force per unit area.	Mechanical Stress,Mechanical Stresses,Stresses, Mechanical
D013997	Time Factors	Elements of limited time intervals, contributing to particular results or situations.	Time Series,Factor, Time,Time Factor