External lamina is a structure similar to

basal lamina The basal lamina is a layer of extracellular matrix secreted by the epithelial cells, on which the epithelium sits. It is often incorrectly referred to as the basement membrane, though it does constitute a portion of the basement membrane. The ba ...

that surrounds the

sarcolemma The sarcolemma (''sarco'' (from ''sarx'') from Greek; flesh, and ''lemma'' from Greek; sheath) also called the myolemma, is the cell membrane surrounding a skeletal muscle fiber or a cardiomyocyte. It consists of a lipid bilayer and a thin out ...

of muscle cells. It is secreted by

myocytes A muscle cell is also known as a myocyte when referring to either a cardiac muscle cell (cardiomyocyte), or a smooth muscle cell as these are both small cells. A skeletal muscle cell is long and threadlike with many nuclei and is called a m ...

and consists primarily of Collagen type IV,

laminin Laminins are a family of glycoproteins of the extracellular matrix of all animals. They are major components of the basal lamina (one of the layers of the basement membrane), the protein network foundation for most cells and organs. The laminin ...

and perlecan (heparan sulfate proteoglycan). Nerve cells, including perineurial cells and Schwann cells also have an external lamina-like protective coating.Wheater's Functional Histology, 5th ed. Young, Lowe, Stevens and Heath. Adipocytes also have an external lamina.

References

Skin anatomy Histology {{anatomy-stub