Biomaterial Database

Proportions of slow-twitch and fast-twitch extrafusal fibers in receptive fields of tendon organs in chicken leg muscles. 1998

A Maier

Department of Cell Biology, University of Alabama at Birmingham, 35294-0019, USA. amaier@cellbio.bhs.uab.edu

Golgi tendon organs are mechanoreceptors that monitor the contractile force produced by motor units. Receptors are most responsive to contractions of extrafusal muscle fibers that terminate closest to them and on them. Three anterior and four posterior chicken leg muscles were examined. Proportions of immunohistochemically identified slow-twitch extrafusal fibers and fast-twitch extrafusal fibers were calculated for 374 tendon organ receptive fields. Tendon organs were observed in muscle regions occupied either by slow-twitch fibers or fast-twitch fibers only, but most were found in regions that contained both slow-twitch and fast-twitch extrafusal fibers. The frequency with which each fiber type occurred near tendon organs approached the frequency with which it occurred in more inclusive regions. In receptive fields with mixed fiber populations, fast-twitch fibers were the predominant type, especially in the anterior leg muscles. Distribution patterns of extrafusal fiber types adjacent to and farther removed from tendon organs suggest that afferent discharges from tendon organs are by and large unbiased measures of the contractile activity of the extrafusal fiber population of the muscle portion in which the tendon organs are located. In mixed muscle regions, slow-twitch fibers and fast-twitch fibers attach on given tendon organs, enabling them to monitor forces produced by slow motor units and by fast motor units. Most tendon organs are situated in mixed extrafusal fiber fields with high fast-twitch fiber content, indicating that in chicken leg muscles sensory feedback from tendon organs is largely one from fast motor units.

UI	MeSH Term	Description	Entries
D008465	Mechanoreceptors	Cells specialized to transduce mechanical stimuli and relay that information centrally in the nervous system. Mechanoreceptor cells include the INNER EAR hair cells, which mediate hearing and balance, and the various somatosensory receptors, often with non-neural accessory structures.	Golgi Tendon Organ,Golgi Tendon Organs,Krause's End Bulb,Krause's End Bulbs,Mechanoreceptor,Mechanoreceptor Cell,Meissner's Corpuscle,Neurotendinous Spindle,Neurotendinous Spindles,Receptors, Stretch,Ruffini's Corpuscle,Ruffini's Corpuscles,Stretch Receptor,Stretch Receptors,Mechanoreceptor Cells,Bulb, Krause's End,Bulbs, Krause's End,Cell, Mechanoreceptor,Cells, Mechanoreceptor,Corpuscle, Meissner's,Corpuscle, Ruffini's,Corpuscles, Ruffini's,End Bulb, Krause's,End Bulbs, Krause's,Krause End Bulb,Krause End Bulbs,Krauses End Bulb,Krauses End Bulbs,Meissner Corpuscle,Meissners Corpuscle,Organ, Golgi Tendon,Organs, Golgi Tendon,Receptor, Stretch,Ruffini Corpuscle,Ruffini Corpuscles,Ruffinis Corpuscle,Ruffinis Corpuscles,Spindle, Neurotendinous,Spindles, Neurotendinous,Tendon Organ, Golgi,Tendon Organs, Golgi
D009218	Myosins	A diverse superfamily of proteins that function as translocating proteins. They share the common characteristics of being able to bind ACTINS and hydrolyze MgATP. Myosins generally consist of heavy chains which are involved in locomotion, and light chains which are involved in regulation. Within the structure of myosin heavy chain are three domains: the head, the neck and the tail. The head region of the heavy chain contains the actin binding domain and MgATPase domain which provides energy for locomotion. The neck region is involved in binding the light-chains. The tail region provides the anchoring point that maintains the position of the heavy chain. The superfamily of myosins is organized into structural classes based upon the type and arrangement of the subunits they contain.	Myosin ATPase,ATPase, Actin-Activated,ATPase, Actomyosin,ATPase, Myosin,Actin-Activated ATPase,Actomyosin ATPase,Actomyosin Adenosinetriphosphatase,Adenosine Triphosphatase, Myosin,Adenosinetriphosphatase, Actomyosin,Adenosinetriphosphatase, Myosin,Myosin,Myosin Adenosinetriphosphatase,ATPase, Actin Activated,Actin Activated ATPase,Myosin Adenosine Triphosphatase
D002645	Chickens	Common name for the species Gallus gallus, the domestic fowl, in the family Phasianidae, order GALLIFORMES. It is descended from the red jungle fowl of SOUTHEAST ASIA.	Gallus gallus,Gallus domesticus,Gallus gallus domesticus,Chicken
D003094	Collagen	A polypeptide substance comprising about one third of the total protein in mammalian organisms. It is the main constituent of SKIN; CONNECTIVE TISSUE; and the organic substance of bones (BONE AND BONES) and teeth (TOOTH).	Avicon,Avitene,Collagen Felt,Collagen Fleece,Collagenfleece,Collastat,Dermodress,Microfibril Collagen Hemostat,Pangen,Zyderm,alpha-Collagen,Collagen Hemostat, Microfibril,alpha Collagen
D005246	Feedback	A mechanism of communication within a system in that the input signal generates an output response which returns to influence the continued activity or productivity of that system.	Feedbacks
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
D000906	Antibodies	Immunoglobulin molecules having a specific amino acid sequence by virtue of which they interact only with the ANTIGEN (or a very similar shape) that induced their synthesis in cells of the lymphoid series (especially PLASMA CELLS).
D018482	Muscle, Skeletal	A subtype of striated muscle, attached by TENDONS to the SKELETON. Skeletal muscles are innervated and their movement can be consciously controlled. They are also called voluntary muscles.	Anterior Tibial Muscle,Gastrocnemius Muscle,Muscle, Voluntary,Plantaris Muscle,Skeletal Muscle,Soleus Muscle,Muscle, Anterior Tibial,Muscle, Gastrocnemius,Muscle, Plantaris,Muscle, Soleus,Muscles, Skeletal,Muscles, Voluntary,Skeletal Muscles,Tibial Muscle, Anterior,Voluntary Muscle,Voluntary Muscles
D018656	Muscle Fibers, Fast-Twitch	Skeletal muscle fibers characterized by their expression of the Type II MYOSIN HEAVY CHAIN isoforms which have high ATPase activity and effect several other functional properties - shortening velocity, power output, rate of tension redevelopment. Several fast types have been identified.	Muscle Fibers, Intermediate,Muscle Fibers, Type II,Muscle Fibers, White,Fast-Twitch Muscle Fiber,Fast-Twitch Muscle Fibers,Fiber, Fast-Twitch Muscle,Fiber, Intermediate Muscle,Fiber, White Muscle,Fibers, Fast-Twitch Muscle,Fibers, Intermediate Muscle,Fibers, White Muscle,Intermediate Muscle Fiber,Intermediate Muscle Fibers,Muscle Fiber, Fast-Twitch,Muscle Fiber, Intermediate,Muscle Fiber, White,Muscle Fibers, Fast Twitch,White Muscle Fiber,White Muscle Fibers
D018657	Muscle Fibers, Slow-Twitch	Skeletal muscle fibers characterized by their expression of the Type I MYOSIN HEAVY CHAIN isoforms which have low ATPase activity and effect several other functional properties - shortening velocity, power output, rate of tension redevelopment.	Muscle Fibers, Red,Muscle Fibers, Type I,Fiber, Red Muscle,Fiber, Slow-Twitch Muscle,Fibers, Red Muscle,Fibers, Slow-Twitch Muscle,Muscle Fiber, Red,Muscle Fiber, Slow-Twitch,Muscle Fibers, Slow Twitch,Red Muscle Fiber,Red Muscle Fibers,Slow-Twitch Muscle Fiber,Slow-Twitch Muscle Fibers