|Diagram of longitudinal sections of medullated nerve fibers.|
|Transverse sections of medullated nerve fibers.|
|Gray's||subject #183 727|
Neurolemma (also neurilemma and sheath of Schwann) is the outermost layer of nerve fibers in the peripheral nervous system. It is a nucleated cytoplasmic layer of Schwann cells that surrounds the myelin sheath of axons.
Unlike the axon and the myelin sheath, the neurolemma does not degenerate after a nerve has been cut or crushed; the hollow tube formed by the neurolemma is instrumental in regenerating the nerve fiber. It is important to note that in CNS, axons are myelinated by oligodendrocytes, thus lack neurolemma.