Faculty Opinions recommendation of Microglia phagocytose myelin sheaths to modify developmental myelination.

Several speculations exist as to the site of incorporation of preformed molecules into myelin. The possibility that an autoradiographic analysis of cholesterol-1,2-H3 incorporation at very short times after injection might shed some light in the solution of that problem led to the present experiment.Cholesterol-1,2-H3 was injected intraperitoneally into 24 tenday old mice. The animals were then sacrificed at 10,20,30,40,60,90,120 and 180 min after the injection and the sciatic nerves were processed for electron microscope autoradiography. To analyze the grain distribution in the autoradiograms of cross and longitudinal sections from each sciatic nerve myelin sheaths were subdivided into three compartments named: outer 1/3, middle 1/3 and inner 1/3 compartments.It was found that twenty min. after the injection of cholesterol -1.2-H3 (Figs. 1 and 2), 55% of the total number of grains (t.n.g) found in myelin were within the outer 1/3 compartment, 9% were within the middle 1/3 and 36% within the inner 1/3 compartment

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Faculty Opinions recommendation of Cdc42 and Rac1 signaling are both required for and act synergistically in the correct formation of myelin sheaths in the CNS.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1046460.496429 ◽

2006 ◽

Author(s):

Genevieve Rougon

Keyword(s):

Myelin Sheaths

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Faculty Opinions recommendation of Visualization of cytoplasmic diffusion within living myelin sheaths of CNS white matter axons using microinjection of the fluorescent dye Lucifer Yellow.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.13335956.14702069 ◽

2011 ◽

Author(s):

Klaus-Armin Nave ◽

Hauke Werner

Keyword(s):

White Matter ◽

Lucifer Yellow ◽

Fluorescent Dye ◽

Myelin Sheaths

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Faculty Opinions recommendation of Individual oligodendrocytes have only a few hours in which to generate new myelin sheaths in vivo.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.718023519.793480212 ◽

2013 ◽

Author(s):

Klaus-Armin Nave ◽

Hauke Werner

Keyword(s):

Myelin Sheaths

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Cortical neurons exhibit diverse myelination patterns that scale between mouse brain regions and regenerate after demyelination

Nature Communications ◽

10.1038/s41467-021-25035-2 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Cody L. Call ◽

Dwight E. Bergles

Keyword(s):

Cortical Neurons ◽

Regional Differences ◽

Brain Regions ◽

Axon Diameter ◽

Neuronal Identity ◽

Cortical Areas ◽

Myelin Sheaths ◽

Parvalbumin Interneurons ◽

Selection Of

ABSTRACTAxons in the cerebral cortex show a broad range of myelin coverage. Oligodendrocytes establish this pattern by selecting a cohort of axons for myelination; however, the distribution of myelin on distinct neurons and extent of internode replacement after demyelination remain to be defined. Here we show that myelination patterns of seven distinct neuron subtypes in somatosensory cortex are influenced by both axon diameter and neuronal identity. Preference for myelination of parvalbumin interneurons was preserved between cortical areas with varying myelin density, suggesting that regional differences in myelin abundance arises through local control of oligodendrogenesis. By imaging loss and regeneration of myelin sheaths in vivo we show that myelin distribution on individual axons was altered but overall myelin content on distinct neuron subtypes was restored. Our findings suggest that local changes in myelination are tolerated, allowing regenerated oligodendrocytes to restore myelin content on distinct neurons through opportunistic selection of axons.

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Biology of the repair of central nervous system demyelinated lesions: an appraisal

Arquivos de Neuro-Psiquiatria ◽

10.1590/s0004-282x1996000200026 ◽

1996 ◽

Vol 54 (2) ◽

pp. 331-334 ◽

Cited By ~ 3

Author(s):

L. A. V Peireira ◽

M. A. Cruz-Höfling ◽

M. S. J. Dertkigil ◽

D. L. Graça

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Schwann Cells ◽

Demyelinating Disease ◽

Experimental Models ◽

Primitive Cell ◽

Marked Influence ◽

Myelin Sheaths ◽

Human Material ◽

The Central Nervous System

The integrity of myelin sheaths is maintained by oligodendrocytes and Schwann cells respectively in the central nervous system (CNS) and in the peripheral nervous system. The process of demyelination consisting of the withdrawal of myelin sheaths from their axons is a characteristic feature of multiple sclerosis, the most common human demyelinating disease. Many experimental models have been designed to study the biology of demyelination and remyelination (repair of the lost myelin) in the CNS, due to the difficulties in studying human material. In the ethidium bromide (an intercalating gliotoxic drug) model of demyelination, CNS remyelination may be carried out by surviving oligodendrocytes and/or by cells differentiated from the primitive cell lines or either by Schwann cells that invade the CNS. However, some factors such as the age of the experimental animals, intensity and time of exposure to the intercalating chemical and the topography of the lesions have marked influence on the repair of the tissue.

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