Title: T-Tubule Function in Mammalian Cardiac Myocytes | Circulation Research
Headings: T-Tubule Function in Mammalian Cardiac Myocytes
T-Tubule Function in Mammalian Cardiac Myocytes
Abstract
Occurrence and Morphology of the T-Tubules
T-Tubule Development Is Labile
Proteins Present in the T-Tubule Membrane
Ca2+-Handling Proteins
Na+-Handling Proteins
K+-Handling Proteins
Anion-Handling Proteins
Second-Messenger Pathways
Interpretation of Immunohistochemical Data
Protein Colocalization Within, and With Proteins Adjacent to, the T-Tubules
Localization of Function
Cells Lacking T-Tubules
Diffusion Studies
Scanning Pipette
Detubulation
Functional Role
Electrical Properties of T-Tubules
Coupling of Ca 2+ Entry and Ca 2+ Release
Ca 2+ Efflux
Signal Transduction
Changes During Development and Disease
T-Tubule Development and Morphology in Hypertrophy and Failure
Changes in Protein Expression in Development, Hypertrophy, and Failure
Relevance of Changes in T-Tubule Structure and Protein Expression to Function
Conclusions and Unanswered Questions
Footnotes
References

Content: 2 Thus, the t-tubular system is not, as its name might suggest, a simple transverse system of tubules but is a complex system of branching tubules with both transverse and longitudinal elements ( Figure 1 ). Because of its complexity, it has been suggested that the transverse-axial tubular system, 14 sarcolemmal Z rete, 2 or sarcolemmal tubule network 11 might be a more appropriate name. However, t-tubule remains the standard term and will be used in the present review, and surface sarcolemma will be used to describe that part of the cell membrane not within the t-tubules. Download figure
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Figure 1. Three-dimensional structure of the t-tubular system in a living rat ventricular myocyte, reconstructed from a stack of images of dextran-linked fluorescein fluorescence within the t-tubules. Bar=5 μm. Reprinted from Soeller C, Cannell MB. Examination of the transverse tubular system in living cardiac rat myocytes by 2-photon microscopy and digital image–processing techniques. Circ Res. 1999;84:266–275, by permission of the American Heart Association ©1999.