Nervous Tissue Staining

Question 1

What are the two anatomical sections of the nervous system?

Answer 1

a) CNS – brain and spinal cord
b) PNS – all other nervous tissue

Question 2

What is the somatic nervous system responsible for?

Answer 2

Voluntary, conscious control

Question 3

What is the autonomic nervous system responsible for?

Answer 3

Involuntary functions

Question 4

What are the three categories of nervous tissue stains?

Answer 4

• Nervous tissue cells and processes
• Glial cells and processes
• Myelin sheath

Question 5

What does Nissl substance consist of?

Answer 5

Basophilic cytoplasmic material found in neurons (RNA)

Question 6

What staining methods are used for Nissl substance?

Answer 6

• Cresyl echt
• Thionin (aniline dyes)

Question 7

What are the two types of nerve cell processes?

Answer 7

• Axons
• Dendrites

Question 8

What is the function of dendrites?

Answer 8

Main location for neuron information input

Question 9

What is the purpose of neuroglia?

Answer 9

Support and insulate neurons in the CNS

Question 10

What are the four types of glial cells?

Answer 10

• Oligodendroglia
• Astroglia
• Microglia
• Ependymal cells

Question 11

What do oligodendroglia do?

Answer 11

Produce myelin sheath in the CNS

Question 12

What is the main role of astrocytes?

Answer 12

Provide physical and nutritional support for neurons

Question 13

What are microglia?

Answer 13

Phagocytic cells located in the brain and spinal cord

Question 14

What is the role of ependymal cells?

Answer 14

Form a selective barrier between CSF and neural tissue

Question 15

What is myelin composed of?

Answer 15

• Protein
• Cerebrosides
• Phospholipids
• Cholesterol

Question 16

What staining method is commonly used for myelin sheath?

Answer 16

Luxol Fast Blue and iron hematoxylin

Question 17

What is the result of the osmium tetroxide method?

Answer 17

Myelin stained black

Question 18

What is Weigert’s method used for?

Answer 18

To stain myelin blue

Question 19

What is the purpose of the Luxol Fast Blue method?

Answer 19

To demonstrate normal myelin

Question 20

What type of staining method is Luxol Fast Blue?

Answer 20

Regressive staining method

Question 21

What is the fixative of choice for Luxol Fast Blue?

Answer 21

10% formalin or K dichromate

Question 22

What are the results expected from a Luxol Fast Blue stain?

Answer 22

• Myelin fibers stain blue
• Nissl substance purple to violet
• Nuclei purple to violet

Question 23

What is the purpose of Weil’s method?

Answer 23

For the demonstration of myelin in tissue

Question 24

What does Mallory’s PTAH stain demonstrate?

Answer 24

Glial cells

Question 25

What is the principle of the Mallory’s PTAH stain?

Answer 25

Phosphotungstic acid binds hematein to provide a blue stain

Question 26

What is the fixative used in Mallory’s PTAH?

Answer 26

10% NBF

Question 27

What is the significance of the staining solution in Mallory’s PTAH?

Answer 27

It stains astrocytes blue

Question 28

How long should sections be decolorized in 95% alcohol?

Answer 28

At least one hour

Question 29

What is the first step after decolorizing sections in 95% alcohol?

Answer 29

Rinse rapidly in 3 changes of distilled water

Question 30

How long should sections be washed in running tap water after staining with KMnO4?

Answer 30

10 minutes

Question 31

How long should sections be stained in PTAH solution?

Answer 31

Overnight at RT

Question 32

In the PTAH staining results, what color do glial cells appear?

Answer 32

Blue

Question 33

What color do neurons stain in the PTAH method?

Answer 33

Salmon

Question 34

Which method demonstrates astrocytes?

Answer 34

Cajal’s method

Question 35

What type of fixative is used for the Cajal method?

Answer 35

Formalin ammonium bromide

Question 36

What is the Bielschowsky method used for?

Answer 36

To stain neurofibrils

Question 37

What are the two types of myelin stains?

Answer 37

* Positive methods (staining degenerating myelin) * Negative methods (staining normal myelin)

Question 38

What are examples of negative myelin stains?

Answer 38

* Luxol Fast Blue * Weil's methods

Question 39

What is a potential hazard of using mercuric chloride?

Answer 39

Extremely toxic and a severe environmental hazard