Title: T-Tubule - an overview | ScienceDirect Topics
Headings: T-Tubule
T-Tubule
Ion Channel Trafficking
T-Tubules
Skeletal Muscle
T-tubules Are Surface Invaginations; the SR Is an Internal Membrane System
Structure and Function of Calcium Release Channels
2 T Tubules and CRUs Revert to More Primitive Forms Under Pathological Conditions
Muscles
Coupling Action Potentials to Contraction
The Cellular Basis of Cardiac Contractility
The SR Releases Stored Ca 2+ to Activate Contraction
Disorders of Muscle Excitability
Calcium couples muscle membrane excitation to filament contraction
Muscle physiology
Excitation–contraction coupling
EXERCISE | Muscle
Voltage-dependent Sarcoplasmic Reticulum Ca 2+ Release

Content: A similar, although more limited, separation of RyR and CaV1.2 clusters is found in a pan triadin null mouse model, where expression levels of all junctional proteins are decreased, with an impairment of e–c coupling and susceptibility to ventricular arrhythmia ( Chopra et al., 2009 ). T tubules in fast fibers of skeletal muscles respond in a very sensitive manner to a number of interventions that also influence the relationship of T tubules to SR and the frequency of CRUs. Disordered T networks with frequent longitudinal extensions; evidence of new T tubule formation and multiple SR–T tubule contacts (pentads, heptads) are found in denervated ( Takekura, Tamaki, Nishizawa, & Kasuga, 2003 ); eccentrically exercised ( Takekura, Fujinami, Nishizawa, Ogasawara, & Kasuga, 2001) and, on a slower time scale, in immobilized muscles ( Takekura, Kasuga, Kitada, & Yoshioka, 1996)
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URL: https://www.sciencedirect.com/science/article/pii/S1063582310660012
Muscles
In Cell Biology (Third Edition), 2017
Coupling Action Potentials to Contraction
The plasma membrane of skeletal muscle cells, like that of nerve cells, is excitable (see Fig. 17.6) but, unlike that in nerves, it invaginates deeply to form T tubules that run across the entire cell ( Fig. 39.13 ). Depending on the species and type of striated muscle (skeletal versus cardiac), T tubules may be located either at the level of the Z disks or at the thick filament ends.