Biomaterial Database

Intersarcomere dynamics during fixed-end tetanic contractions of frog muscle fibres. 1979

F J Julian, and D L Morgan

1. The stability of sarcomere lengths along single twitch fibres from frog muscles was examined during fixed-end tetani, using a spot follower apparatus to monitor the length of a central segment. 2. Internal movement, with most of the fibre lengthening and small regions at the ends shortening as the contraction proceeded, was always seen at fibre lengths beyond those corresponding to a sarcomere length of 2.3 micrometer. 3. The rate of lengthening of the central region was fastest during the slow phase of tension rise (creep) but continued at a slower rate throughout the tetanus. These observations are in accord with the idea that progressive development of sarcomere non-uniformity is responsible for the creep phase. 4. Observations at various muscle lengths of the rate of decay of tension and the duration of the slow phase of relaxation suggest that movement during relaxation is due to sarcomere length non-uniformities and variations of decay rate with sarcomere length. 5. The rate of tension fall after stimulation ceases in an isometric sarcomere, and the factors which determine that rate, are discussed in view of evidence from fixed-end and length-clamped tetani, and recently reported experiments using aequorin.

UI	MeSH Term	Description	Entries
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
D011896	Rana temporaria	A species of the family Ranidae occurring in a wide variety of habitats from within the Arctic Circle to South Africa, Australia, etc.	European Common Frog,Frog, Common European,Common European Frog,Common Frog, European,European Frog, Common,Frog, European Common
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
D001001	Anura	An order of the class Amphibia, which includes several families of frogs and toads. They are characterized by well developed hind limbs adapted for jumping, fused head and trunk and webbed toes. The term "toad" is ambiguous and is properly applied only to the family Bufonidae.	Bombina,Frogs and Toads,Salientia,Toad, Fire-Bellied,Toads and Frogs,Anuras,Fire-Bellied Toad,Fire-Bellied Toads,Salientias,Toad, Fire Bellied,Toads, Fire-Bellied
D001696	Biomechanical Phenomena	The properties, processes, and behavior of biological systems under the action of mechanical forces.	Biomechanics,Kinematics,Biomechanic Phenomena,Mechanobiological Phenomena,Biomechanic,Biomechanic Phenomenas,Phenomena, Biomechanic,Phenomena, Biomechanical,Phenomena, Mechanobiological,Phenomenas, Biomechanic
D066298	In Vitro Techniques	Methods to study reactions or processes taking place in an artificial environment outside the living organism.	In Vitro Test,In Vitro Testing,In Vitro Tests,In Vitro as Topic,In Vitro,In Vitro Technique,In Vitro Testings,Technique, In Vitro,Techniques, In Vitro,Test, In Vitro,Testing, In Vitro,Testings, In Vitro,Tests, In Vitro,Vitro Testing, In