Neurolemma

Neurolemma
Diagram of longitudinal sections of medullated nerve fibers.
Transverse sections of medullated nerve fibers.
Gray's	subject #183 727
MeSH	A08.561.600

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.

External links

• Histology at dmacc.edu

Histology: nervous tissue
Neurons (gray matter)	soma, axon (axon hillock, axoplasm, axolemma, neurofibril/neurofilament), dendrite (Nissl body, dendritic spine, apical dendrite, basal dendrite) types (bipolar, pseudounipolar, multipolar, pyramidal, Purkinje, granule)
Afferent nerve/Sensory nerve/Sensory neuron	GSA, GVA, SSA, SVA, fibers (Ia, Ib or Golgi, II or Aβ, III or Aδ or fast pain, IV or C or slow pain)
Efferent nerve/Motor nerve/Motor neuron	GSE, GVE, SVE, Upper motor neuron, Lower motor neuron (α motorneuron, γ motorneuron)
Synapses	neuropil, synaptic vesicle, neuromuscular junction, electrical synapse - Interneuron (Renshaw)
Sensory receptors	Free nerve ending, Meissner's corpuscle, Merkel nerve ending, Muscle spindle, Pacinian corpuscle, Ruffini ending, Olfactory receptor neuron, Photoreceptor cell, Hair cell, Taste bud
Glial cells	astrocyte, oligodendrocyte, ependymal cells, microglia, radial glia
Myelination (white matter)	Schwann cell, oligodendrocyte, nodes of Ranvier, internode, Schmidt-Lanterman incisures, neurolemma
Related connective tissues	epineurium, perineurium, endoneurium, nerve fascicle, meninges