The picture above shows the location of oligodendrocytes in relationship to neurons (yellow).
Oligodendrocytes are glial cells that are similar to astrocytes. They are support cells found in the spinal chord and brain, and their somata (cell body) can be about 12-14 micrometers in diameter. Their main job is to produce myelin which is made in both the central nervous system (CNS) and peripheral nervous system (PNS). However, oligodendrocytes are only responsible for myelin production in the CNS, while Schwann cells produce myelin in the PNS. The above picture shows the two different cells and where they are located. Myelin is very important in the CNS as it is a fatty substance that insulates and protects the gaps in the sheath of the neuron. If the axons in a neuron did not have myelin, the action potential or charge when an impulse moves along the axon would be continuous along the sheath, rather than just at the nodes of Ranvier.
Oligodendrocytes are generally circular in shape and are divided into three parts: the cell body, the cytoplasmic processes, and the myelin segments. The cell body is the main part of the oligodendrocyte and it contains the nucleus, which is generally dark and oval-shaped and has a cluster of chromatin inside. The cell body has the same organelles that are in all eukaryotic cells. The cell's processes are what form the myelin segments that cover the axons. Lastly, the myelin segments are circles around the axon that insulate the axon. There are two main types of oligodendrocytes: 1. satellite cells that are around neurons in gray matter, form the outer layer of the cerebrum, and maintain the ion balance in neurons and 2. myelin-producing cells in the white matter.
The following image illustrates the structure of an oligodendrocyte as described above:
First, I really like how your post was organized so we could see the location of oilgodendrocytes. It was interesting for me to read about this cell because I didn't even know it existed. It was great how you specified that it was only responsible for myelin production in the CNS and that Schwann cells were in the PNS.
ReplyDeleteWow, the shape of these cells are very interesting. What are in the little arm things protruding from the cell body?
ReplyDeleteI liked how you included the things in parenthesis to really help the reader understand everything!
ReplyDeleteThe attention you paid to detail really helps show the greatness of the cell and its function. Also the pictures were much easier to understand and were more useful because you explained the cell so well.
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