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Normal·Cardiovascular·Myocardium

Cardiac muscle — intercalated discs

Stain: H&E·Magnification: 40x·Tissue: Cardiac muscle·3 labeled regions
Cardiac muscle — intercalated discs histology — Cardiovascular, Myocardium, H&E
Wikimedia Commons · File:Dogcardiacmuscle400.jpg · https://commons.wikimedia.org/wiki/File:Dogcardiacmuscle400.jpg (CC-licensed)
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Description

Striated branching fibers with central nuclei. Intercalated discs (gap junctions + desmosomes) couple cells electrically and mechanically — the functional syncytium of the heart.

Labeled regions (3)

  1. 1
    Intercalated disc

    Stair-step junction — contains gap junctions, desmosomes, fascia adherens.

  2. 2
    Central nucleus

    Single, ovoid, central — distinguishes from skeletal (peripheral).

  3. 3
    Striations

    Sarcomeres confirm cardiac is striated, unlike smooth.

More cardiovascular histology

Atherosclerosis — fibrous cap + lipid core
Atherosclerosis — fibrous cap + lipid core
Artery (aorta/coronary)