Title: T-tubule - Wikipedia
Headings: T-tubule
T-tubule
Contents
Structure
Regulators
Function
Excitation-contraction coupling
Calcium control
Detubulation
History
Clinical significance
See also
References

Content: T-tubule - Wikipedia
T-tubule
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Invagination of the plasma membrane of a muscle cell that extends inward from the cell surface around each myofibril; the ends of T-tubules make contact with the sarcoplasmic reticulum membrane
T-tubule
Skeletal muscle, with T-tubule labelled in zoomed in image. T-tubule structure and relationship to the sarcoplasmic reticulum in skeletal muscle
Details
Part of
Cell membrane of skeletal muscle and cardiac muscle cells. Identifiers
Latin
tubulus transversus
TH
H2.00.05.2.01018, H2.00.05.2.02013
Anatomical terminology
T-tubules ( transverse tubules) are extensions of the cell membrane that penetrate into the centre of skeletal and cardiac muscle cells. With membranes that contain large concentrations of ion channels, transporters, and pumps, T-tubules permit rapid transmission of the action potential into the cell, and also play an important role in regulating cellular calcium concentration. Through these mechanisms, T-tubules allow heart muscle cells to contract more forcefully by synchronising calcium release throughout the cell. T-tubule structure and function are affected beat-by-beat by cardiomyocyte contraction, as well as by diseases, potentially contributing to heart failure and arrhythmias. Although these structures were first seen in 1897, research into T-tubule biology is ongoing. Contents
1 Structure
1.1 Regulators
2 Function
2.1 Excitation-contraction coupling
2.2 Calcium control
2.3 Detubulation
3 History
4 Clinical significance
5 See also
6 References
Structure
T-tubules are tubules formed from the same phospholipid bilayer as the surface membrane or sarcolemma of skeletal or cardiac muscle cells. They connect directly with the sarcolemma at one end before travelling deep within the cell, forming a network of tubules with sections running both perpendicular (transverse) to and parallel (axially) to the sarcolemma.