neurolemma

Information about neurolemma

Diagram of longitudinal sections of medullated nerve fibers.
Transverse sections of medullated nerve fibers.
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.

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Histology: nervous tissue
Neurons (gray matter)soma, axon (axon hillock, axoplasm, axolemma, neurofibril/neurofilament), dendrite (Nissl body, dendritic spine)
types (bipolar, pseudounipolar, multipolar, pyramidal, Purkinje, granule)
Afferent nerve/Sensory nerve/Sensory neuronGSA, 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 neuronGSE, GVE, SVE, Upper motor neuron, Lower motor neuron (Aα motorneuron, Aγ motorneuron)
Synapsesneuropil, synaptic vesicle, neuromuscular junction, electrical synapse - Interneuron (Renshaw)
Sensory receptorsFree nerve ending, Meissner's corpuscle, Merkel nerve ending, Muscle spindle, Pacinian corpuscle, Ruffini ending, Olfactory receptor neuron, Photoreceptor cell, Hair cell, Taste bud
Glial cellsastrocyte, oligodendrocyte, ependymal cells, microglia, radial glia
Myelination (white matter)Schwann cell, oligodendrocyte, nodes of Ranvier, internode, Schmidt-Lanterman incisures, neurolemma
Related connective tissuesepineurium, perineurium, endoneurium, nerve fascicle, meninges
Medical Subject Headings (MeSH) is a huge controlled vocabulary (or metadata system) for the purpose of indexing journal articles and books in the life sciences. Created and updated by the United States National Library of Medicine (NLM), it is used by the MEDLINE/PubMed
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axon or nerve fiber, is a long, slender projection of a nerve cell, or neuron, that conducts electrical impulses away from the neuron's cell body or soma.

Anatomy


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The Peripheral nervous system resides or extends outside the "CNS" central nervous system (the brain and spinal cord) to serve the limbs and organs. Unlike the central nervous system, however, the PNS is not protected by bone, leaving it exposed to toxins and mechanical injuries.
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nucleus (3) ribosome (4) vesicle (5) rough endoplasmic reticulum (ER) (6) Golgi apparatus (7) Cytoskeleton (8) smooth ER (9) mitochondria (10) vacuole (11) cytoplasm (12) lysosome (13) centrioles]]

In cell biology, the nucleus (pl.
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Cytoplasm is a gelatinous, semi-transparent fluid that fills most cells. Eukaryotic cells contain a nucleus that is kept separate from the cytoplasm by a double membrane layer. The cytoplasm has three major elements; the cytosol, organelles and inclusions.
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Named after the German physiologist Theodor Schwann, Schwann cells (also referred to as neurolemmocytes) are a variety of glial cell that mainly provide myelin insulation to axons in the peripheral nervous system of jawed vertebrates.
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Myelin is an electrically insulating phospholipid layer that surrounds the axons of many neurons. It is an outgrowth of glial cells: Schwann cells supply the myelin for peripheral neurons while oligodendrocytes supply it to those of the central nervous system.
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axon or nerve fiber, is a long, slender projection of a nerve cell, or neuron, that conducts electrical impulses away from the neuron's cell body or soma.

Anatomy


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Oligodendrocyte

General Information
Tissue type Nervous
Cell type Neuroglia
Location Central nervous system
Role Myelination
Identification Robertson, 1899
Ultrastructure
Soma size
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Histology (from the Greek ἱστός) is the study of tissue sectioned as a thin slice, using a microtome. It can be described as microscopic anatomy.
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Nervous tissue is the fourth major class of vertebrate tissue. The function of the nervous tissue is in communication between parts of the body. It is composed of neurons, which transmit impulses, and the neuroglia, which assist propagation of the nerve impulse as well as provide
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Neurons (also known as neurones and nerve cells) are electrically excitable cells in the nervous system that process and transmit information. In vertebrate animals, neurons are the core components of the brain, spinal cord and peripheral nerves.
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"Gray Matter"
Author Stephen King
Language English
Genre(s) Horror, science fiction
Published in Cavalier (1st release) ,
Night Shift,
Arbour House Necropolis
Publication type Magazine
Media type Print
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The soma, or perikaryon, is the bulbous end of a neuron, containing the cell nucleus. It is also known as the cell body. The word soma is Greek, meaning "body"; the soma of a neuron is often called the "cell body".
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axon or nerve fiber, is a long, slender projection of a nerve cell, or neuron, that conducts electrical impulses away from the neuron's cell body or soma.

Anatomy


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Axon Hillock is the anatomical part of a neuron that connects the cell body called soma (biology) to the axon. It is attributed as the place where Inhibitory Postsynaptic Potentials (IPSPs) and Excitatory Postsynaptic Potentials (EPSPs) from numerous synaptic inputs on the
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Axoplasm is the cytoplasm within the axon of a neuron. Neural processes (axons and dendrites) contain about 99.6% of the cell’s cytoplasm, and 99.7% of that is in the axons (Sabry et al., 1995).
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The axolemma is the membrane of a neuron's axon. It is responsible for maintaining the cell's membrane potential, and it contains channels through which ions can flow. This changes the voltage inside the axon and can depolarize or hyperpolarize the cell.
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Identifiers
Symbol NEFH

Entrez 4744
HUGO 7737
OMIM 162230

RefSeq NM_021076
UniProt P12036
Other data

Locus Chr. 22 q12.1-13.
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For the dendritic crystal structure, see .


Dendrites (from Greek dendron, “tree”) are the branched projections of a neuron that act to conduct the electrical stimulation received from other neural cells to the cell body, or
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Nissl body (or Nissl granule or tigroid body) is a large granular body found in nerve cells. It was named after Franz Nissl, German neurologist (1860-1919).
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A dendritic spine is a small (sub-micrometre) membranous extrusion that protrudes from a dendrite and forms one half of a synapse. Typically spines have a bulbous head (the spine head) which is connected to the parent dendrite through a thin spine neck.
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A bipolar cell is a type of neuron which has two extensions. Bipolar cells are specialized sensory neurons for the transmission of special senses. As such, they are part of the sensory pathways for smell, sight, taste, hearing and vestibular functions.
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A pseudounipolar neuron (pseudo - false, uni - one) is a sensory neuron in the peripheral nervous system. This neuron contains a long dendrite and a short axon that connects to the spinal cord.
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A multipolar neuron is a type of neuron that possesses a single (usually long) axon and many dendrites, allowing for the integration of a great deal of information from other neurons. These dendritic branches can also emerge from the nerve cell body.
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Location Cortex esp. Layers III and V
Function excitatory projection neuron
Neurotransmitter Glutamate
Morphology Multipolar Pyramidal
Presynaptic connections Superficial cortical layers
Postsynaptic connections Varies (see text)
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Location Cerebellum
Function inhibitory projection neuron

Morphology flat dendritc arbor
Presynaptic connections Parallel fibers and Climbing fibers
Postsynaptic connections Cerebellar deep nuclei

Purkinje cells (or
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granule cells refer to tiny neurons (a type of cell) that are around 10 micrometres in diameter. Granule cells are found within the granular layer of the cerebellum, layer 4 of cerebral cortex, the dentate gyrus of the hippocampus, and in the olfactory bulb.
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afferent neurons--otherwise known as sensory or receptor neurons--carry nerve impulses from receptors or sense organs toward the central nervous system. This is the case vice versa as well. This term can also be used to describe relative connections between structures.
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Sensory nerves are nerves that receive sensory stimuli, such as how something feels and if it is painful.

They are made up of nerve fibers, called sensory fibers (mechanoreceptor fibers sense body movement and pressure placed against the body, and nociceptor fibers sense
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