Supporting cells of the nervous system Flashcards
Ciliated cells lining the ventricles of the brain and central canal of the spinal cord.
Ependymal cells.
What is the role of ependymal cells with regards to CSF?
Formation and circulation of CSF.
These cells play a role in directing cell migration during brain development, forming and circulating CSF.
Ependymal cells.
Phagocytes that engulf debris and are involved in remodelling of synaptic connections.
Microglia.
These cells may migrate into the brain from blood. Also contribute to relationship between immune system and CNS function.
Microglia.
Name two types of macroglia found in the CNS.
- Astrocytes.
- Oligodendrocytes.
Name two types of macroglia found in the PNS.
- Schwann cells.
- Capsular cells.
The most numerous cells in the nervous system and highly heterogeneous in morphology.
Astrocytes.
The perivascular end-feet of astrocytes are found where and contribute to what?
Surrounding the capillaries that form the blood brain barrier.
Subpial end-feet on the surface of the brain and spinal cord are processes of which cell of the nervous system?
Astrocytes.
Astrocytes undergo alterations in response to CNS insults making them highly susceptible to what?
Neoplasm formation.
Astrocytes control electrolyte balance in the CNS, particularly of which ion?
Extracellular K+.
This cell produces the neurotrophins necessary for neuronal survival.
Astrocytes.
Responsible for the uptake of several important neurotransmitters e.g. glutamate, GABA.
Astrocytes.
Cells supplying Glutamine for the synthesis of the neurotransmitter Glutamate by neurones.
Astrocytes.
Cells that regulate the “tightness” of the blood brain barrier.
Astrocytes.`
The processes of these cells form the myelin sheath that wraps around axons in the CNS in a spiral.
Oligodendrocytes.
What do oligodendrocytes produce that is important for the repair of damaged CNS axons?
Neurotrophic factors e.g. nerve growth factor.
Loss of which cell contributes to Multiple Sclerosis and causing multiple neurological symptoms.
Oligodendrocytes.
Loss of myelin causes failure of what?
Saltatory conduction
Why does saltatory conduction fail when loss of myelin occurs?
There are no voltage-activated sodium channels in the area of axon previously covered by the oligodendrocyte process.
Each Schwann cell envelops what?
A short segment of one axon in the PNS.
What is the gap between each Schwann cell known as?
The node of Ranvier.
Action potentials jump the node of Ranvier using what type of conduction?
Saltatory
Schwann cells spiral around an axon to form what?
Lamellae
What is the outmost lamella of the Schwann cell known as?
Neurolemma or sheath of Schwann.
To regenerate transected axons these cells proliferate to form a tube into which growth sprouts of the proximal end of the cut axon enter and re-innervate the de-innervated target.
Schwann cells.
Glial elements that surround the neuronal cell bodies in sensory and autonomic ganglia.
Capsular / Satelitte cells.
Flattened cells forming an almost complete layer separating ganglion cell bodies of DRG and some cranial nerves from surrounding non-neural connective tissue and vascular structure.
Capsular/ Satellite cells.
- DRG = dorsal root ganglion.
Capsular/satelitte cells are thought to have a similar role to which cells of the CNS?
Astrocytes.
Cells present around the cell bodies of autonomic ganglion as an incomplete layer - particularly in the sympathetic division.
Capsular/satellite cells.
