Schmidt-Lanterman incisures
Encyclopedia
In the peripheral nervous system
(PNS) axons can be either myelinated or unmyelinated. Myelination means that the axon is insulated by surrounding layers of fatty membrane (myelin
) produced by Schwann cells. These layers are continuous (like rolling up rope), but, due to the way they are formed, they often include small amounts of Schwann cell
cytoplasm
not displaced to the periphery during Schwann cell
formation of the myelin. These are the so called Myelin incisures or Schmidt-Lanterman clefts (a.k.a. Schmidt-Lanterman incisures,clefts of Schmidt-Lanterman, segments of Lanterman, medullary segments), which subdivide the myelinated axon into irregular portions.
They are histological
evidence of the small amount of cytoplasm that remains in the inner layer of the myelin sheath created by Schwann cell
s wrapping tightly around a nerve
.
Peripheral nervous system
The peripheral nervous system consists of the nerves and ganglia outside of the brain and spinal cord. The main function of the PNS is to connect the central nervous system to the limbs and organs. Unlike the CNS, the PNS is not protected by the bone of spine and skull, or by the blood–brain...
(PNS) axons can be either myelinated or unmyelinated. Myelination means that the axon is insulated by surrounding layers of fatty membrane (myelin
Myelin
Myelin is a dielectric material that forms a layer, the myelin sheath, usually around only the axon of a neuron. It is essential for the proper functioning of the nervous system. Myelin is an outgrowth of a type of glial cell. The production of the myelin sheath is called myelination...
) produced by Schwann cells. These layers are continuous (like rolling up rope), but, due to the way they are formed, they often include small amounts of Schwann cell
Schwann cell
Schwann cells or neurolemmocytes are the principal glia of the peripheral nervous system . Glial cells function to support neurons and in the PNS, also include satellite cells, olfactory ensheathing cells, enteric glia and glia that reside at sensory nerve endings, such as the Pacinian corpuscle...
cytoplasm
Cytoplasm
The cytoplasm is a small gel-like substance residing between the cell membrane holding all the cell's internal sub-structures , except for the nucleus. All the contents of the cells of prokaryote organisms are contained within the cytoplasm...
not displaced to the periphery during Schwann cell
Schwann cell
Schwann cells or neurolemmocytes are the principal glia of the peripheral nervous system . Glial cells function to support neurons and in the PNS, also include satellite cells, olfactory ensheathing cells, enteric glia and glia that reside at sensory nerve endings, such as the Pacinian corpuscle...
formation of the myelin. These are the so called Myelin incisures or Schmidt-Lanterman clefts (a.k.a. Schmidt-Lanterman incisures,clefts of Schmidt-Lanterman, segments of Lanterman, medullary segments), which subdivide the myelinated axon into irregular portions.
They are histological
Histology
Histology is the study of the microscopic anatomy of cells and tissues of plants and animals. It is performed by examining cells and tissues commonly by sectioning and staining; followed by examination under a light microscope or electron microscope...
evidence of the small amount of cytoplasm that remains in the inner layer of the myelin sheath created by Schwann cell
Schwann cell
Schwann cells or neurolemmocytes are the principal glia of the peripheral nervous system . Glial cells function to support neurons and in the PNS, also include satellite cells, olfactory ensheathing cells, enteric glia and glia that reside at sensory nerve endings, such as the Pacinian corpuscle...
s wrapping tightly around a nerve
Nerve
A peripheral nerve, or simply nerve, is an enclosed, cable-like bundle of peripheral axons . A nerve provides a common pathway for the electrochemical nerve impulses that are transmitted along each of the axons. Nerves are found only in the peripheral nervous system...
.