An early post-traumatic reaction of lymph-heart striated muscle fibers in adult frogRana temporariaduring the first postoperative week: An electron microscopic and autoradiographic study

2015 ◽  
Vol 276 (12) ◽  
pp. 1525-1534 ◽  
Author(s):  
Marina I. Krylova ◽  
Dmitry S. Bogolyubov
1968 ◽  
Vol 46 (2) ◽  
pp. 213-219 ◽  
Author(s):  
D. C. Gayton ◽  
J. A. M. Hinke

Chloride-sensitive Ag–AgCl microelectrodes were inserted into single striated muscle fibers of the giant barnacle, Balanus nubilus, to measure the activity of Cl− in the myoplasm, (aCl)i. Chemical analysis was also carried out to determine the total concentration of Cl− in the fiber, [Cl]i. In two sets of experiments, (aCl)i was 28.8 and 22.4 mM while [Cl]i was 75.1 and 66.8 mmoles/kg fiber water respectively. The transmembrane Cl− potential, calculated from the aCl measurements in the myoplasm and the bath, was slightly less than the membrane potential. To locate the large fraction of fiber Cl− that is not free in the myoplasm, Cl− washout studies were done in constant [K]o[Cl]o product Ringer solutions in which [Cl]o was reduced to 50% and 25% of the normal concentration. Fibers which were soaked in these solutions for 30 min showed no change in (aCl)i but a large drop in [Cl]i. From the extent of this drop, it was calculated that these muscle fibers have an extracellular space of about 5% of fiber volume. Electron microscopic studies indicate that this space is comprised of large clefts and smaller tubules which penetrate deeply into the fiber.


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

1981 ◽  
Vol 111 (3) ◽  
pp. 240-246 ◽  
Author(s):  
Jesús G. Ninomiya ◽  
Olga M. Echeverría ◽  
Gerardo H. Vázquez-Nin

2007 ◽  
Vol 11 (5) ◽  
pp. 375-381 ◽  
Author(s):  
Giuseppe Coppolino ◽  
Davide Bolignano ◽  
Sergio Parisi ◽  
Emanuele Aloisi ◽  
Adolfo Romeo ◽  
...  

1972 ◽  
Vol 59 (1) ◽  
pp. 103-120 ◽  
Author(s):  
C. G. dos Remedios ◽  
R. G. C. Millikan ◽  
M. F. Morales

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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