Biomaterial Database

Obliquely striated muscle. 3. Contraction mechanism of Ascaris body muscle. 1967

J Rosenbluth

Segments of the obliquely striated body muscle of Ascaris were fixed at minimum body length after treatment with acetylcholine and at maximum body length after treatment with piperazine citrate and then studied by light and electron microscopy. Evidence was found for two mechanisms of length change: sliding of thin filaments with respect to thick filaments such as occurs in cross-striated muscle, and shearing of thick filaments with respect to each other such that the degree of their stagger increases with extension and decreases with shortening. The shearing mechanism could account for great extensibility in this muscle and in nonstriated muscles in general and could underlie other manifestations of "plasticity" as well. In addition, it is suggested that the contractile apparatus is attached to the endomysium in such a way that the sarcomeres can act either in series, as in cross-striated muscle, or individually. Since the sarcomeres are virtually longitudinal in orientation and are almost coextensive with the muscle fiber, it would, therefore, be possible for a single sarcomere contracting independently to develop tension effectively between widely separated points on the fiber surface, thus permitting very efficient maintenance of isometric tension.

UI	MeSH Term	Description	Entries
D008853	Microscopy	The use of instrumentation and techniques for visualizing material and details that cannot be seen by the unaided eye. It is usually done by enlarging images, transmitted by light or electron beams, with optical or magnetic lenses that magnify the entire image field. With scanning microscopy, images are generated by collecting output from the specimen in a point-by-point fashion, on a magnified scale, as it is scanned by a narrow beam of light or electrons, a laser, a conductive probe, or a topographical probe.	Compound Microscopy,Hand-Held Microscopy,Light Microscopy,Optical Microscopy,Simple Microscopy,Hand Held Microscopy,Microscopy, Compound,Microscopy, Hand-Held,Microscopy, Light,Microscopy, Optical,Microscopy, Simple
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
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
D010879	Piperazines	Compounds that are derived from PIPERAZINE.
D003239	Connective Tissue Cells	A group of cells that includes FIBROBLASTS, cartilage cells, ADIPOCYTES, smooth muscle cells, and bone cells.	Cell, Connective Tissue,Cells, Connective Tissue,Connective Tissue Cell
D000109	Acetylcholine	A neurotransmitter found at neuromuscular junctions, autonomic ganglia, parasympathetic effector junctions, a subset of sympathetic effector junctions, and at many sites in the central nervous system.	2-(Acetyloxy)-N,N,N-trimethylethanaminium,Acetilcolina Cusi,Acetylcholine Bromide,Acetylcholine Chloride,Acetylcholine Fluoride,Acetylcholine Hydroxide,Acetylcholine Iodide,Acetylcholine L-Tartrate,Acetylcholine Perchlorate,Acetylcholine Picrate,Acetylcholine Picrate (1:1),Acetylcholine Sulfate (1:1),Bromoacetylcholine,Chloroacetylcholine,Miochol,Acetylcholine L Tartrate,Bromide, Acetylcholine,Cusi, Acetilcolina,Fluoride, Acetylcholine,Hydroxide, Acetylcholine,Iodide, Acetylcholine,L-Tartrate, Acetylcholine,Perchlorate, Acetylcholine
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
D001200	Ascaris	A genus of nematodes of the superfamily ASCARIDOIDEA whose species usually inhabit the intestine.	Ascari