Health and medicine
Oligodendrocytes are glia cells in the central nervous system that serve multiple functions. Most importantly, they create the myelin sheath around neuron axons, which allows for faster and more efficient communication between neurons. Oligodendrocytes also interact with other cells to exchange substances and may have additional, less-understood functions. Created by Matthew Barry Jensen.
Want to join the conversation?
- Why would one neuron need to be insulated from another? You mentioned that the oligodendrocytes insulate the axons of the nerve cells(8 votes)
- Good question. The neurons are not insulated from one another, but rather the oligodendrocytes use a lipid based myelin sheath to insulate the CNS axons in order to increase the speed and efficiency of their action potential. The myelin sheath is wrapped around the axon and allows the action potential to "skip" over itself, thus the action potential needs only to depolarize the nodes or "spaces" between the myelin sheath. I hope this helped to answer your question.(22 votes)
- is it right that oligodendrocytes produces myeline sheath that surrounded axon in CNS and schwann cell produces myeline sheath in PNS ?(3 votes)
- Yes, the oligodendrocytes produce myelin sheaths in the CNS and Schwann cells produce myelin sheaths in the PNS. However, one other thing of note: a single oligodendrocyte can myelinate multiple neuronal axons, while a single Schwann cell can only myelinate a single nueron's axon.(5 votes)
- how much charge do neurons produce? is it possible to be electrocuted from inside the body if there wasnt insulation?(1 vote)
- They use in the order of magnitude of millivolts. If you think that the resting potential of a cell is approx. -70mV and when it depolarizes it might reach a peak of approx. +40mV, that's only a potential difference of around 110mV! Your neurons cannot light up a light bulb let alone give you an electric shock. But it's plenty for the nervous system to do its job.(1 vote)
- can an oligodendrocyte be connected to more than one myelin sheath on an axon?(2 votes)
- Yes, a single oligodendrocyte can myelinate multiple axons from different neurons.(1 vote)
- How long does it take to create the myelin sheath? Does it happen continuously in every part of the nervous system or does the growth occur in waves/stages and regionally?(1 vote)
- Are all axons in the CNS myelinated?(1 vote)
- No, some axons are unmyelinated and this may be for pathways involving pain perception etc.(1 vote)
- I am studying 2'3 cyclic nucleotide 3' phosphodiesterase ( cnp) is a oligodedrocyte, that means that it mylinates but how? Also how are oligodendrocytes and shwann cells connected?(1 vote)
- At2:46, which specific substances exchanged influence the glial cells, neural, and oligodendrocytes?(1 vote)
- I am not sure that my question is related to this video.
My question is the thickness of the myelin sheath affects the speed of transmitting the signal through the neuron.
If it is too thick or thin, is there any problems on our body.(1 vote)
- I do not know of an issue with the myelin being too thick. However, if the myelin sheath is damaged by toxins such as lead, or mercury, if there is a chronic lack of Vit B 12 and or if it is attacked by infection or by unknown causes such as Multiple Sclerosis, then the action potential can not travel correctly, and neurotransmitters are not released. Symptoms depend on the area of the injury but in general weakness, lack of connected thought etc. is likely. To read more, check out Wikipedia, an open encyclopedia that should be verified with other sources. https://en.wikipedia.org/wiki/Myelin#Demyelination(1 vote)
In this video, I want to talk about oligodendrocytes. Oligodendrocytes are glia of the central nervous system, derived from neural stem cells and named from Greek words for cells with a few branches. To show the structure of oligodendrocytes, let me first draw a few neurons. I'll just draw their somas and axons and I'll leave off their dendrites. I'll draw the somas for a couple of oligodendrocytes, one here and one here. And each oligodendrocyte will extend a few processes, maybe up to a few dozen processes each, towards the axons of neurons. And the structures at the end of these oligodendrocyte processes will be the myelin sheath for neurons that have a myelin sheath on their axons. And you can see that each oligodendrocyte can be creating segments of myelin sheath for the axons of multiple neurons. And the different segments of myelin sheath can be from different oligodendrocytes on any particular neuron's axon. This material of myelin is composed mostly of lipid, which is the same kind of substance that makes up fat. So this is kind of a fatty sheath around some of the axons of certain neurons. So let's take a little closer look at this over here. And what we'll do is we'll kind of cut through the soma and the process in one of these segments of myelin sheath, kind of like this. And then we're going to look at it end-on, like we're looking down from the end of the axon. So here, I'll draw the axon. And we've cut it. So we're looking at it end-on. So we're looking down the tube of the axon. And the myelin sheath is just the membrane at the end of the process of the oligodendrocyte, that's wrapped very thinly around the axon many, many, many times, like a roll of tape. And I like to think of these like the rubber coating on a wire, kind of insulating the axon. And we'll get into how information is transmitted along axons in other videos. But basically, this makes the transmission of information faster and more efficient. And the myelin sheath is still connected by the process to the soma of the oligodendrocyte to maintain it. So each oligodendrocyte process forms one segment of myelin on an axon. And each oligodendrocyte may myelinate multiple axons. In addition to this function of creating the myelin sheath, oligodendrocytes also appear to influence neurons and other glia, and vice versa, through exchange of a variety of substances. There are also some variably-shaped nonmyelinating oligodendrocytes in parts of the central nervous system. But their function is not yet entirely clear.