Special Stains

Question 1

Van Gieson’s trichrome - what colour is and what stains collagen and muscle?

Answer 1

Collagen - red (acid fuchsin)

Muscle - yellow (picric acid), also muscle, RBCs

Question 2

What stains fungi in Grocott’s?

Answer 2

Methenamine silver

Question 3

2 special requirements when using Oil Red O

Answer 3

• Cryostat sections (paraffin removes lipids)

- Aqueous mounting (xylene dissolves lipids)

Question 4

Metachromatic stain that stains mast cell granules purple

Answer 4

Toluidine blue

Question 5

2 components of ammoniacal silver

Answer 5

Silver nitrate

Ammonium hydroxide

Question 6

What does the gold chloride (toning) step do?

Answer 6

Replace silver (brown) with gold (black), which is more stable

Question 7

This reagent is added to prevent light-induced silver precipitate

Answer 7

Sodium thiosulphate

Question 8

What does Masson-Fontana stain demonstrate? What’s its counterstain?

Answer 8

Melanin (via silver)

Neutral red

Question 9

This step is required to precipitate invisible silver precipitates in reticulin method

Answer 9

Formalin treatment