Biomaterial Database

Structure of motor endplates in the different fiber types of vertebrate skeletal muscles. 1988

T Ogata

Department of Surgery, Kochi Medical School, Japan.

The number and localization of vertebrate motor endplates on the muscle fiber, and their structure, vary according to phylum and species, and among the different fiber types in a given species. Vertebrate skeletal muscle fibers are classified into two major groups: the twitch (fast) and the slow (tonic) fibers. The twitch fiber has straight Z-lines and a well developed T-SR system, and is singly innervated with en plaque (plate-like) type motor endplate. The twitch fibers are further subdivided into three types: the red (mitochondria-rich), intermediate (mitochondria-moderate) and white (mitochondria-poor) fibers. The motor endplate of the white fiber is large and has a complicated structure, that of the red fiber is small and less complicated, and that of the intermediate fiber possesses intermediate characteristics. The slow fiber has zigzag Z-lines and poorly developed sarcoplasmic reticulum (SR), and is multiply innervated with en grappe (grape-like) type motor endplates. The morphological features of the motor endplate in each of these fiber types of the mammalian, avian, reptilian, amphibian, and fish skeletal muscles are reviewed. Special emphasis has been placed on the three-dimensional structure of the motor endplates of the different fiber types as observed by high-resolution scanning electron microscopy.

UI	MeSH Term	Description	Entries
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
D009045	Motor Endplate	The specialized postsynaptic region of a muscle cell. The motor endplate is immediately across the synaptic cleft from the presynaptic axon terminal. Among its anatomical specializations are junctional folds which harbor a high density of cholinergic receptors.	Motor End-Plate,End-Plate, Motor,End-Plates, Motor,Endplate, Motor,Endplates, Motor,Motor End Plate,Motor End-Plates,Motor Endplates
D009132	Muscles	Contractile tissue that produces movement in animals.	Muscle Tissue,Muscle,Muscle Tissues,Tissue, Muscle,Tissues, Muscle
D009410	Nerve Degeneration	Loss of functional activity and trophic degeneration of nerve axons and their terminal arborizations following the destruction of their cells of origin or interruption of their continuity with these cells. The pathology is characteristic of neurodegenerative diseases. Often the process of nerve degeneration is studied in research on neuroanatomical localization and correlation of the neurophysiology of neural pathways.	Neuron Degeneration,Degeneration, Nerve,Degeneration, Neuron,Degenerations, Nerve,Degenerations, Neuron,Nerve Degenerations,Neuron Degenerations
D009469	Neuromuscular Junction	The synapse between a neuron and a muscle.	Myoneural Junction,Nerve-Muscle Preparation,Junction, Myoneural,Junction, Neuromuscular,Junctions, Myoneural,Junctions, Neuromuscular,Myoneural Junctions,Nerve Muscle Preparation,Nerve-Muscle Preparations,Neuromuscular Junctions,Preparation, Nerve-Muscle,Preparations, Nerve-Muscle
D012104	Reptiles	Cold-blooded, air-breathing VERTEBRATES belonging to the class Reptilia, usually covered with external scales or bony plates.	Reptilia,Reptile
D005399	Fishes	A group of cold-blooded, aquatic vertebrates having gills, fins, a cartilaginous or bony endoskeleton, and elongated bodies covered with scales.
D006652	Histological Techniques	Methods of preparing tissue for examination and study of the origin, structure, function, or pathology.	Histologic Technic,Histologic Technics,Histologic Technique,Histologic Techniques,Histological Technics,Technic, Histologic,Technics, Histologic,Technique, Histologic,Techniques, Histologic,Histological Technic,Histological Technique,Technic, Histological,Technics, Histological,Technique, Histological,Techniques, Histological
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000663	Amphibians	VERTEBRATES belonging to the class amphibia such as frogs, toads, newts and salamanders that live in a semiaquatic environment.	Amphibia,Amphibian