Select Page

Neuroglia – The Army of The Nervous System

Neuroglia – The Army of The Nervous System

Have you ever heard the saying,

Behind every successful man is an even more successful wife?

The same concept applies to neuroglia:

  • Glial cells are the unsung heroes without which neurons would be totally useless and unable to survive.

Behind every successful neuron is an “army” of even more awesome glial cells. — MagR

So today we’re gonna do a rundown of the glial cells!

Neuroglia: Function and Definition

First, let’s make things clear:

Neuroglia = Glia = Glial cells (yes, with an L at the end).

Three different names referring to the same type of cell. (I used to be quite confused until I finally realized that these are three names referring to the same object–as if there weren’t enough words to remember in neuroanatomy as it is…)

Neuroglia are way more numerous then neurons; “an army for a commander.”

 Neuroglia Function

1. Support Nutrition: Some glial are involved in providing the neurons with nutrients by transporting molecules from the blood to the neuron. (Satellite cells and Macroglia)

2. Poison Defense: Some glial cells support the role of “blood brain barrier.” They will simply block most harmful substances from ever reaching the neuron. (Without this barrier, most molecules in the blood would become deadly poisons!)

3. Support electrical communication:

a. Ion concentration regulator: Neuroglia regulate the amount of ions around the neurons. As such they make sure that the neurons environment is optimal for the transmission of the electric pulse. (Learn more about electric signal conduction)

b. Myelin Sheath creation: Some glia are responsible for creating and repairing the myelin sheath around the axon of the neuron. The myelin sheath is what ensures fast / salutatory propagation of the electric signal) (Oligodendrocyte and Schwann cells)

4. EMT services: Some neuroglia proliferate and rush to a site of injury within the central nervous system. (Microglia)

5. Other functions, including structural function, that we will not go into detail.

Types of Neuroglia

Are you ready to absorb even more vocab? Here we go!

In the Central Nervous System (~in the brain)

Cells of the Central Nervous System

Here we have 3 main types of glial cells (Macroglia, Microglia and Ependymal glia) with sub-categories and sub-sub categories:

A. Macroglia

  • Macro – stands for “big.” These cells are “bigger” than other glial cells.

Macroglia are divided into two sub-categories: The Astrocytes and the Oligodendrocytes.

1. Astrocytes

As the prefix implies – Astro means star, astrocytes look like stars with lots of branches (look similar to dendrites – but they are NOT dendrites!)

Astrocytes have two sub-categories themselves:

a. Protoplasmic astrocytes

 They are found in the gray matter

b. Fibrous astrocytes – They are found in the while matter.

2. Oligodendrocytes

The prefix “oligo” means “few”, and “dendro” sounds like “dendrites”. Basically this cell looks like an astrocyte except that it is a little smaller, and has only a few branches.

Oligodendrocytes have 3 sub-categories (I told you this would be tough – I’ll try to make it short!):

a.  Satellite oligodendrocyte – Myelin sheath creation

b. Interfascicular oligodendrocyte – They are found in between axons (“inter”) and can “myelinate” more than one axon at a time.

c. Vascular oligodendrocyte – They are found close to small capillaries.

B. Microglia

These are the smallest types of glia (they are micro!) This small size is what allows them to proliferate around a site of injury in the CNS

C. Ependymal glia

They are involved in neuronal development.

  • Mnemonic for the CNS: “Mark And Peter Found Online Some Indian Veal – Micro Epic.”

(Macroglia Astroctyte Protoplasmic Fibrous Oligodendrocyte Satellite Intrafascicular Vascular – Microglia Ependymal)

We’re almost finished! We only have two types of neuroglia left in the Peripheral Nervous System (PNS).

In the Peripheral Nervous System (~spinal cord)

A. Satellite cells (don’t confuse them with the satellite oligodendrocytes). These have similar functions as the Macroglia we just covered.

B. Schwann cells(I love the name… Sounds so pretty). These glial cells are responsible for creating and repairing the myelin sheath of axons in the PNS. They can only myelinate one axon at a time

OK! We’re done!

Minimum to Remember About Neuroglia

Neuroglia

Their function:

  1.  Support nutrition
  2.  Poison Defense
  3.  Support electrical communication
  4.  EMT services
  5.  And much, much more…. 🙂

Types of Neuroglia

– too many!

  • Once you remember the name and what they mean you can recall 90% of what we just covered. Use the chart I prepared for you if it helps!

Mnemonic for neuroglia in the CNS: Mark And Peter Found Online Some Indian Veal – Micro Epic.

 

If you want more articles and videos about the Nervous System, you can find them here. More resources are available to help make Biology fun. I invite you to absorb all the content you can find here at Interactive-Biology.com.


About The Author

205 Shares
Share13
Pin192
Tweet
Share
+1