Glial Cells Flashcards
1
Q
What is glial
A
Provides structural support to the CNS.
- Provides a protective environment for fragile neurons
- Large number = 50x more glia than there are neurons
- Able to undergo mitosis
2
Q
What is astrocytes?
A
- Most abundant
- Cover capillaries regulating the formation and maintenance of the blood-brain barrier by the tight junctions between capillary endothelial cells.
- Regulate ions (K & H & water)
- Main sites of glycogenesis and glycogen reserves (energy)
- Assists in formation and maintenance of synapses
3
Q
Astrocytes absorb what?
A
Excess neurotransmitter at synapses, especially glutamate and GABA.
Produces neurotrophic factors important in neuronal survival.
4
Q
What is microglial cells?
A
In CNS and small
-Phagocytic - go to site of injury and engulf dead and damaged cells.
5
Q
What is ependymal cells?
A
In CNS
- Line the ventricles of the brain and central canal of the spinal cord
- Produce CSF by forming a complex with capillaries called the choroid plexus in the ventricles
- Cilia to help circulate CSF
6
Q
What is oligodendroglial Cells?
A
In CNS
-Cell membrane forms myelin (insulator)
-Processes that wrap around sections of multiple axons
increases nerve conduction velocity (good)
Impedes axon regeneration (bad)
7
Q
What is Schwann Cells?
A
Only glial cell in PNS -Cell membrane forms myelin -Processes that wrap around sections of 1 to a few axons Increases conduction velocity (good) Assists in axon regeneration (good)
