Histology: Central Nervous System Flashcards Preview

Pathology > Histology: Central Nervous System > Flashcards

Flashcards in Histology: Central Nervous System Deck (30):
1

What are the cells of neuroectodermal origin?

- Neurons
- Glial Cells

Cells of neuroectodermal origin include neurons and glial cells (astrocytes, oligodendrocytes, ependymocytes).

2

What are the cells of mesenchymal origin?

- Microglia/macrophages
- Meninges
- Choroid plexus

Cells of mesenchymal origin include microglia/macrophages, cells of the meninges, and cells of the choroid plexus.

3

What is found in the cerebral cortex gray matter?

Cell bodies, synapses and dendrites

4

What is found in the cerebral cortex white matter?

Myelinated axons

5

Gray matter covers the white matter in the ___________

Cerebral Cortex - this is opposite in the spinal cord.

6

What does Nissl stain stain?

Rough endoplasmic reticulum

7

What are the characteristics of motor neurons (size, axon length, etc)?

– Large cell body
– Have long axons
– Nucleus with single large nucleolus
– Prominent Nissl substance

8

What are the characteristics of interneurons (local circuit)?

– Small compact cell body
– Lack Nissl substance
– Short dendrites and small axons

9

What is the role of the principal neurons?

They have long axons and transmit information over long distances - an example are the motor neurons

10

What is central chromatolysis?

In response to destruction of axons - neuronal cell body balloons and nucleus is displaced to the periphery with the dispersion of the ribonucleoprotein

11

Neurophagia

Damage to the cell body directly may lead to it beyond surrounded by microglial cells - commonly seen in viral infections

12

Acute Neuronal Injury

Irreversible injury with cell body shrinkage and increased cytoplasmic eosinophilia and loss of nuclear chromatin

13

Where is the nucleus seen in a ballooned neuron?

Still remains central

14

Negri Body Association

Rabies

15

Lewy Body Association

Parkinson's Disease

16

Hirano Body Association

Alzheimer's Disease but also noted in normal individuals with aging

17

Function of Astrocytes

Aid with structure and repair of damaged neurons

18

What are the main types of astrocytes?

- Fibrillary
- Protoplasmic

19

Fibrillary Astrocytes

White matter – majority with
numerous and extensive processes

20

Protoplasmic Astrocytes

Gray matter – fewer branches

21

Gliosis

A non specific nervous system reaction to injury and involves hypertrophy of astrocytes

22

Function of Oligodendrocytes

Maintenance of function of myelin sheaths

23

Are there glia in the peripheral nervous system?

NO. Schwann cells will perform the functions of the oligodendrocytes.

24

What happens with loss of oligodendrocytes?

Leads to demyelination

25

Microglia

Not "true" glia - they are monocytes that are CD68+ and act as phagocytic and Ag-presenting cells

26

Where are microglia found?

Found evenly in the gray and white matter

27

Ependyma

Specialized glia that line the ventricles and have cilia - no basement membrane is present though

28

What is the function of ependyma?

Mainly as barrier between the brain and CSF

29

Choroid Plexus

Made of folds of CSF secreting ependymal cells that protrude into the ventricles

30

Pia Mater

Thin layer over the brain and the spinal cord

Decks in Pathology Class (203):