Week 2 - A - Pharmacology 1b - Supporting cells of the nervous system

Question 1

Glial cells are the major majority of cells in the CNS What glial cell is the main immune surveillance cell in the CNS?

Answer 1

Microglia - phagocytic type cell that engulfs debris

Question 2

What is the function of the astrocytes, Schwann cells and oligodendrocytes? What is the broader category for the astrocytes, schwann cells and oligodendroyctes? What is the other cell type in this broad category?

Answer 2

Astrocytes are involved in electrolyte balance and maintaining the tightness of the blood brain barrier Schwann cells produce myelin in the PNS Oligodendrocytes produce myelin in the CNS They fall under a broader category called macroglia Other cell type in macroglia are Capsular (satellite) cells

Question 3

What do astrocytes supply for synthesis of neurotransmitter glutamate by neurones?

Answer 3

They supply glutamine

Question 4

What is the most abundant cell type in the nervous system?

Answer 4

This would be the astrocytes

Question 5

Loss of oligodendrocytes (in part due to autoimmune attack) contributes to which disorder? What are the main symptoms?

Answer 5

Multiple sclerosis Motor weakness, loss of co-ordination and visual disturbances mainly

Question 6

The PNS equivalent of the oligodendrocyte, but each Schwann cell envelops only a short segment of one axon Myelination of an entire axon requires a chain of Schwann cells. The gap between these is the Node of Ranvier between which action potentials ‘jump’ in saltatory conduction Inflammatory demyelination of peripheral neurones may be triggered by a variety of bacterial, or viral, infections What is the syndrome known as?

Answer 6

This is Guillain Barrer Syndrome

Question 7

What is the function of the capsular (satellite) cell?

Answer 7

The surround the neuronal cell bodies ins sensory and autonomic neurones

Question 8

What is the function of ependymal cells?

Answer 8

They are ciliated cells that line the ventricles of the brain and central canal of the spinal cord - they move the CSF

Question 9

Name the different glial cells in both the pns and cns

Answer 9

* PNS

• Schwann cells - myelin
• Capsular (satellite cells) - surround neuronal cell bodies

* CNS

• Oligodendrocytes - myelin
• Astrocytes - maintain BBB and regulate homeostasis
• Microglia - main immune surveillance cell of CNS
• Ependymal - line choroid ventricles