scholarly journals SARCOLEMMAL INVAGINATIONS CONSTITUTING THE T SYSTEM IN FISH MUSCLE FIBERS

1964 ◽  
Vol 22 (3) ◽  
pp. 675-696 ◽  
Author(s):  
Clara Franzini-armstrong ◽  
Keith R. Porter
Keyword(s):  
Fine Structure ◽  
Osmium Tetroxide ◽  
Striated Muscle ◽  
Muscle Fibers ◽  
Fish Muscle ◽  
Structural Features ◽  
The Body ◽  
Glutaraldehyde Fixation ◽  
Striated Muscle Fibers ◽  
T System

Striated muscle fibers from the body and tail myotomes of a fish, the black Mollie, have been examined with particular attention to the sarcoplasmic reticulum (SR) and transverse tubular (or T) system. The material was fixed in osmium tetroxide and in glutaraldehyde, and the images provided by the two kinds of fixatives were compared. Glutaraldehyde fixes a fine structure that is broadly comparable with that preserved by osmium tetroxide alone but differs in some significant details. Especially significant improvements were obtained in the preservation of the T system, that is, the system of small tubules that pervades the fiber at every Z line or A-I junction level. As a result of this improved glutaraldehyde fixation, the T system is now clearly defined as an entity of fine structure distinct from the SR but uniquely associated with the SR and myofibrils. Glutaraldehyde fixation also reveals that the T system is a sarcolemmal derivative that retains its continuity with the sarcolemma and limits a space that is in direct communication with the extracellular environment. These structural features favor the conclusion that the T system plays a prominent role in the fast intracellular conduction of the excitatory impulse. The preservation of other elements of muscle fine structure, including the myofibrils, seems for reasons discussed, to be substantially improved by glutaraldehyde.

Medulloblastoma with striated muscle fibers

1973 ◽  
Vol 38 (5) ◽  
pp. 642-646 ◽  
Author(s):  
Anthony J. Lewis
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Striated Muscle ◽  
Muscle Fibers ◽  
Malignant Gliomas ◽  
The Body ◽  
Content Type ◽  
Striated Muscle Fibers ◽  
Fine Print ◽  
Stimulation Of

✓ A case is reported in which a medulloblastoma showed evidence of striated muscle fibers. Fifteen additional cases of primary central nervous system (CNS) tumor containing muscle fibers (excluding teratomas) are reviewed. These tumors appear to be of mesenchymal, rather than teratoid, origin, and to be related to embryonal sarcomas (mesenchymomas) in other parts of the body. It is postulated that the presence of such fibers in malignant gliomas may be due to rhabdomyoblast-inducing action of mesenchyme, analogous to the fibroblastic stimulation observed in desmoplastic medulloblastomas, and the massive stimulation of perivascular tissue often associated with undifferentiated astrocytomas.

scholarly journals The Ultrastructure of Myosin-Extracted Striated Muscle Fibers

1967 ◽  
Vol 7 (3) ◽  
pp. 499-504 ◽  
Author(s):  
BENJAMIN WALCOTT ◽  
ELLIS B. RIDGWAY
Keyword(s):  
Striated Muscle ◽  
Muscle Fibers ◽  
Striated Muscle Fibers

Morphological Studies of Fiber Types of Striated Muscle Fibers of the Cremaster in the Guinea Pig

1981 ◽  
Vol 111 (3) ◽  
pp. 240-246 ◽  
Author(s):  
Jesús G. Ninomiya ◽  
Olga M. Echeverría ◽  
Gerardo H. Vázquez-Nin
Keyword(s):  
Guinea Pig ◽  
Striated Muscle ◽  
Muscle Fibers ◽  
Fiber Types ◽  
Morphological Studies ◽  
Striated Muscle Fibers

Experimental Therapies in Renal Replacement: The Effect of Two Different Potassium Acetate-free Biofiltration Protocols on Striated Muscle Fibers

2007 ◽  
Vol 11 (5) ◽  
pp. 375-381 ◽  
Author(s):  
Giuseppe Coppolino ◽  
Davide Bolignano ◽  
Sergio Parisi ◽  
Emanuele Aloisi ◽  
Adolfo Romeo ◽  
...  
Keyword(s):  
Striated Muscle ◽  
Muscle Fibers ◽  
Potassium Acetate ◽  
Experimental Therapies ◽  
Striated Muscle Fibers

scholarly journals Polarization of Tryptophan Fluorescence from Single Striated Muscle Fibers

1972 ◽  
Vol 59 (1) ◽  
pp. 103-120 ◽  
Author(s):  
C. G. dos Remedios ◽  
R. G. C. Millikan ◽  
M. F. Morales
Keyword(s):  
Sarcomere Length ◽  
Striated Muscle ◽  
Muscle Fibers ◽  
Tryptophan Fluorescence ◽  
Thin Filaments ◽  
A Value ◽  
Striated Muscle Fibers ◽  
Types Of Muscle Fibers ◽  
Cross Bridges ◽  
Contraction And Relaxation

Instrumentation has been developed to detect rapidly the polarization of tryptophan fluorescence from single muscle fibers in rigor, relaxation, and contraction. The polarization parameter (P⊥) obtained by exiciting the muscle tryptophans with light polarized perpendicular to the long axis of the muscle fiber had a magnitude P⊥ (relaxation) > P⊥ (contraction) > P⊥ (rigor) for the three types of muscle fibers examined (glycerinated rabbit psoas, glycerinated dorsal longitudinal flight muscle of Lethocerus americanus, and live semitendinosus of Rana pipiens). P⊥ from single psoas fibers in rigor was found to increase as the sarcomere length increased but in relaxed fibers P⊥ was independent of sarcomere length. After rigor, pyrophosphate produced little or no change in P⊥, but following an adenosine triphosphate (ATP)-containing solution, pyrophosphate produced a value of P⊥ that fell between the contraction and relaxation values. Sinusoidal or square wave oscillations of the muscle of amplitude 0.5–2.0% of the sarcomere length and frequency 1, 2, or 5 Hz were applied in rigor when the myosin cross-bridges are considered to be firmly attached to the thin filaments. No significant changes in P⊥ were observed in either rigor or relaxation. The preceding results together with our present knowledge of tryptophan distribution in the contractile proteins has led us to the conclusion that the parameter P⊥ is a probe of the contractile state of myosin which is probably sensitive to the orientation of the myosin S1 subfragment.

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