This article will go over what glial cells do in the brain and nerves in the body.
You’ll also learn about conditions that are related to glial cells.
Glial cells are like a secretarial pool for yournervous systemand its janitorial and maintenance staff.
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The “astro” part of the name is because the cells have projections that make them look star-shaped.
There are different kinds of astrocytes.
For example,protoplasmic astrocyteshave thick projections with lots of branches.Fibrous astrocyteshave long, slender arms with few branches.
Oligodendrocytes
Oligodendrocytes come from neural stem cells.
The word is made up of a few Greek terms that mean “cells with several branches.”
The main purpose of oligodendrocytes is to help information move faster along axons in the brain.
Oligodendrocytes look like spikey balls.
This protective layer is called themyelin sheath.
The sheath is not continuous, though.
There’s a gap between each membrane that’s called the “node of Ranvier.”
This node helps electrical signals spread efficiently along nerve cells.
Signals along myelinated nerves can travel as fast as 200 miles per second.
Oligodendrocytes also provide stability and carry energy from blood cells to the axons.
Spinal cord injuries can also damage myelin sheaths.
Other diseases associated with oligodendrocyte dysfunction include:
Glutamate Damage
Oligodendrocytes can be damaged by the neurotransmitterglutamate.
Microglia
Microglia are tiny glial cells (“micro” means small).
They act as the brain’s own dedicated immune system.
Microglia are alert to signs of injury and disease.
When microglia respond to an injury, it causes inflammation as part of the healing process.
Sometimes, the response causes problems.
Our brains create a lot of connections between neurons that allow them to pass information back and forth.
They also make cerebrospinal fluid and have an important role in the blood-brain barrier.
Ependymal cells are very small and line up tightly to form the membrane.
Cerebrospinal fluid delivers nutrients to and eliminates waste products from the brain and spinal column.
It also serves as a cushion and shock absorber between your brain and skull.
Radial Glia
Radial glia is believed to be a punch in of stem cell.
This jot down of cell can create other cells.
In the developing brain, stem cells are the “parents” of neurons, astrocytes, and oligodendrocytes.
When you were an embryo, these cells also provided the “scaffolding” for developing neurons.
They provide the long fibers that guide young brain cells into place as your brain forms.
Later in life, these cells contribute to your brain’s ability to change and adapt (neuroplasticity).
Schwann Cells
Schwann cells are named for Theodor Schwann, the physiologist who discovered them.
They function a lot like oligodendrocytes by providing myelin sheaths for axons.
However, Schwann cells are found in the peripheral nervous system (PNS) rather than the CNS.
Instead of being a central cell with membrane-tipped arms, Schwann cells form spirals directly around the axon.
Schwann cells are also part of the PNS’s immune system.
We’re just beginning to learn about satellite cells but many researchers believe they’re similar to astrocytes.
However, they’re found in the PNS, not the CNS.
Summary
There are several kinds of glial cells in your brain and the nerves throughout your body.
Each throw in has a specialand importantjob in keeping your brain working at its best.
Some glial cells help transmit information in the brain.
For example, astrocytes and oligodendrocytes both play important roles in helping neurons “talk” to each other.
Glial cells that are damaged won’t be able to do their jobs wellif at all.
The effects of glial cell dysfunction depend on what role they play in the brain.
For example, if Schwann cells are not working correctly, it can contribute to chronic pain.
The overactivation of microglia may cause inflammation that’s possibly linked to Alzheimer’s brain changes.
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