The tubular vacuolation process in amphibian skeletal muscle

@article{Fraser2004TheTV,
  title={The tubular vacuolation process in amphibian skeletal muscle},
  author={James A. Fraser and Jeremy N. Skepper and Austin R. Hockaday and Christopher L.-H. Huang1},
  journal={Journal of Muscle Research \& Cell Motility},
  year={2004},
  volume={19},
  pages={613-629}
}
The exposure of amphibian muscle to osmotic shock through the introduction and subsequent withdrawal of extracellular glycerol causes ‘vacuolation’ in the transverse tubules. Such manoeuvres can also electrically isolate the transverse tubules from the surface (‘detubulation’), particularly if followed by exposures to high extracellular [Ca2+] and/or gradual cooling. This study explored factors influencing vacuolation in Rana temporaria sartorius muscle. Vacuole formation was detected using… 
Persistent tubular conduction in vacuolated amphibian skeletal muscle following osmotic shock
TLDR
The findings reconcile reports associating detubulation with vacuolation in osmotically shocked muscle with the persistence of tubular electrical activity in extensively vacuolated amphibian fibres following fatigue.
Cardiac glycosides inhibit detubulation in amphibian skeletal muscle fibres exposed to osmotic shock
TLDR
Findings support a scheme in which the osmotic shock initiates a metabolically dependent fluid expulsion that distends the transverse tubules into vacuoles that in turn lead to fibre detubulation.
OSMOTIC PROCESSES IN VACUOLATION AND DETUBULATION OF SKELETAL MUSCLE
TLDR
The vacuolation can be demonstrated under both phase contrast and confocal microscopy following membrane stresses produced by abrupt osmotic manipulations of the external solution (Westerblad and Lannergren, 1990; Krolenko et al., 1995).
Separation of detubulation and vacuolation phenomena in amphibian skeletal muscle
TLDR
It is demonstrated that fibre vacuolation and detubulation are phenomena that are potentially separable through varying the conditions of osmotic shock, withdetubulation requiring significantly more stringent conditions than vacuolated.
Detubulation abolishes membrane potential stabilization in amphibian skeletal muscle
TLDR
A model that contrastingly suggests a T-tubular location for cation--Cl− co-transporter activity or its regulation is suggested, when taken together with previous reports of significant Cl− conductances in the surface membrane.
Detubulation experiments localise delayed rectifier currents to the surface membrane of amphibian skeletal muscle fibres
TLDR
It is suggested that the surface as opposed to the tubular membrane contributes the greater part of the delayed rectifier current in amphibian skeletal muscle.
Membrane potential stabilization in amphibian skeletal muscle fibres in hypertonic solutions
TLDR
A model that implicates the NCC and/or NKCC in fluxes that maintain [Cl−]i above its electrochemical equilibrium is suggested, which splinting of [Cl‐]i in combination with the high PCl/PK of skeletal muscle stabilizes Em despite volume changes produced by extracellular hypertonicity, but at the expense of a cellular capacity for regulatory volume increases (RVIs).
Loop diuretics inhibit detubulation and vacuolation in amphibian muscle fibres exposed to osmotic shock
TLDR
Findings implicate Na-K-Cl co-transport in the water entry into muscle fibres that would be expected following introduction of extracellular glycerol in amphibian skeletal muscles, phenomena also observed in muscular dystrophy.
About the T-system in the myofibril-free sarcoplasm of the frog muscle fibre.
Development of T‐tubular vacuoles in eccentrically damaged mouse muscle fibres
TLDR
It is proposed that T‐tubules are liable to rupture during eccentric contraction probably because of the relative movement associated with the inhomogeneity of sarcomere lengths and when the sodium is pumped from the cell by the sodium pump, the volume load of Na+ and water exceeds the capacity of the T‐ Tubules and causes vacuole production.
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TLDR
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TLDR
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