Muscle Tissue Histology

Smooth muscle (HE) Skeletal muscle (cross section HE) Skeletal muscle (longitudinal section HE) Cardiac muscle (HE) Cardiac muscle (iron-hematoxylin)

Smooth muscle HM, 40x (HE) Smooth muscle cell (one nucleus, thin, bobbin shape) The cells arranged in fasciculi. The nucleus is localised in the centre of the cell. There are no striated

Smooth muscle nucleus

The functional unit of it is the muscular fibre There is a fusion of the myoblast cells during the ontogenesis The number of nuclei may be more than 100

Skeletal muscle cross section, 20x (HE)

Perimysium (Cohnheim field)

Epimysium

Endomysium

Skeletal muscle cross section, 40x (HE)

The bands, which are dyed dark, show a double refraction of light. That s why these are Anisotropes (A) The bands, which are dyed light, have single refraction of light Isotropes (I) There is a thin line in the middle of the I-band, which is called Z-band There is a lighter line in the middle of the A-band, which is called H-band and int he middle of this lighter line there is a dark line, the M-line. The I-band becomes shorter when the muscle contracts

Those contractile elements which show striated pattern is called myofibrils. The place which is between two Z-bands is called sarcomer The myofibrillum consists of myofilaments. thin (9 nm actin) thick (12-15 nm myosin)

Skeletal muscle (longitudinal Harántcs íkolt izom section, 40x (HE) Fibrocyte nucleus

Striated pattern

HM, 40x (HE) Muscle cell nuclei

Cardiac muscle HE 60x Single musle cells, there are cell connecting structures at the end of them Three other cardiac musle cell can attach to one cardiac muscle cell (Y-shape) Eberth s- lines, striated pattern

Cardiac muscle EM 29500x We differenciate between two part lines because of the terraced structure Transversal part: fascia adherens desmosomes

Longitudinal part: nexus (gap-junction) they are responsible for ionic traffic

Cardiac muscle 60x

nucleus

Eberth s-line