Striated Muscle-Psoas Muscle

Longitudinal sections through muscle fibers clearly depict the characteristic striation, i.e., the regular pattern of alternating light and dark cross-bands.  The length of striate d skeletal muscle f ibers ranges from a few millimeters to about 25 cm. Dependent on location and function, they are between 10 and 10 0 μm thick . The tub e-like sarcolemma covers each muscle fiber. The constituents of the sarcolemma are the plasmalemma, the basal lamina and a tight covering of delicate reticular fibers. The outer border of this very delicate fibril network and the connective tissue of the endomysium 1 interconnect. Ever y muscle fiber contains numerous rod-shape d or oval nuclei in the cell periphery, close to the sarcolemma.  Note on nomenclature: in descriptions of electron microscopic images, only the plasmalemma of muscle fibers is termed “sarcolemma.”

1 Endomysium

Stain: azan; magnification: × 500

References

Kuehnel, W.(2003). Color Atlas of Cytology, Histology, and Microscopic Anatomy. 4^th edition . Institute of Anatomy Universitätzu Luebeck Luebeck, Germany . Thieme Stuttgar t · New York .