- Intercalated disc
An intercalated disc is an undulating double membrane separating adjacent cells in
cardiac muscle fibers. Intercalated discs support synchronized contraction of cardiac tissue. They can easily be visualized by a longitudinal section of the tissue.Three types of membrane junctions exist within an intercalated disc—
fascia adherens ,macula adherens (aka desmosomes), andgap junction s.* "Fascia adherens" are anchoring sites for
actin , and connects to the closestsarcomere .* "Macula adherens" stop separation during contraction by binding intermediate filaments joining the cells together also called a desmosome.
* "Gap junctions" allow
action potential s to spread between cardiac cells by permitting the passage of ions between cells, producingdepolarization of the heart muscle.When observing cardiac tissue through a microscope, intercalated discs are an identifying feature of cardiac muscle.
ee also
*
Gap junction
*Cardiac muscle External links
*
* - "Ultrastructure of the Cell: cardiac muscle, intercalated disk "
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