Showing posts with label macroglia. Show all posts
Showing posts with label macroglia. Show all posts

Tuesday, August 30, 2011

Glial Cells/Neuroglia

This is another post for those of you trying to study the nervous system.

Source



What are Glial cells and why are they important?

Glial cells also called neuroglia are non-neuronal cells that maintain homeostasis, form myelin and provide support and protection for the brain’s neurons.
There are two types:

Microglia – protect the neurons of the central nervous system. They are capable of phagocytosis (meaning they are phagocyte). They are found in all regions of the brain and spinal cords. Their main role is to multiply when the brain is damaged. 
Macroglia
Source
 – contains 4 different types of cells from the central nervous system:
  1. astrocytes
  2. oligodendrocyts
  3. ependymal
  4. radial glia
-         contain 3 types of cells from the peripheral nervous system

Astrocytes:
- they have a very important role in the central nervous system
- are star shaped
- they are the most numerous cells in the central nervous system
- they can be found at the exterior of the brain and spinal cord
-they give biochemical support of endothelial cells that form the blood-brain barrier
-during brain damage or radiation they are the first affected cells

Oligodendrocyts:
-         their main function is to form and maintain myelin

      Schwann Cells
-         they have a similar function to oligodentrocytes
-         their main function is to produce myelin
-         between two cells there is a gap which formes the node of Ranvier
-         their role is also to regenerate destroyed neurons (the broken part of the axon is destroyed and the one from the cell body forms a structure that will be the next axon)

     Satellite cells:
-surround neurons in sensory, sympathetic and parasympathetic ganglia

The main function of neuroglia or glial cell is to repair injuries of the central nervous system. Some will occupy the space left by injured neurons, like astrocytes while others will help repair the neuron, like oligodendrocytes. Schwann cells help the nerve regenerate. So you can see that all these cells have a very important role in neuronal organization.