CHAPTER 19:

STAINING OF LIPIDS
1. It refers to all fats and fat like, or fat 10. It is composed of fatty acids and hexoses,
containing substances. possessing characteristics of both lipids and
- Lipids carbohydrates.
- Glycolipids
2. Lipids of fats are classified into three
classification and these are what? 11. Glycolipids are stained by what stains?
- Simple lipids - Sudan Black B
- Compound lipids - PAS techniques
- Derived lipids
12. It is derived from hydrolysis of simple and
3. What are the esters of fatty acids with compound lipids.
alcohol? - Derived Lipids
- Simple lipids
13. It is distributed throughout the body in
4. Simple lipids are usually found in the body distinct “white” and “brown” adipose tissue
as energy stores in ___________. depots.
- Adipose Lipids - Adipose tissue or fats

5. These are esters of fatty acids with glycerol 14. What is an adipose tissue that is largely
constituents, serving as storage fats in composed of unilocular lipid-filled
animals with high solubility for certain non- adipocytes that specialize in lipid storage?
ionic colored substances (lysochromes) - White Adipose Tissue (WAT)
stainable by Sudan Black B, Sudan IV and
Oil Red 0. 15. What is an adipose tissue that is largely
- Triglycerides composed of multilocular adipocytes that
specialize in lipid burning?
6. These consist of fatty acids, an alcohol and - Brown Adipose Tissue (BAT)
one or more other group such as phosphorus
or nitrogen. 16. Fat cells appear as “__________” on H&E
- Compound lipids stain because large lipid droplet displace the
nucleus and remainder of the cytoplasm to
7. Compound lipids are generally found in the the edge of the cell.
_____________________. - Signet rings
- Central Nervous System
17. With the standard methods of fixation, what
8. They are important components of cellular are the largely lost from tissues during
membranes particularly found in processes.
mitochondria and nervous tissue elements. - Lipids
- Phospholipids
18. What are the other names for Lipid bodies?
9. Phospholipids are readily stained by what - Lipid droplets
stain or dye? - Adiposomes
- Sudan Black B
- Acid Hematin 19. They are distributed in the cytoplasm as
roughly spherical organelles lacking a
 CHAPTER 19:
STAINING OF LIPIDS
delimiting classical bilayer membrane, but
surrounded by an outer monolayer of 29. Lipochrome can be demonstrated by
phospholipids, which at least in some cells ____________ which also stains for
may have a unique fatty acid composition. melanin.
- Lipid Bodies - Schmorl’s Method
30. Lipochrome may also exhibit a strong
20. Cytoplasmic lipid droplets are ________, orange auto fluorescence in formalin-fixed,
usually triacylglycerols or cholesteryl esters. unstained paraffin sections. True or false.
- Neutral Lipids - True

21. Lipids are easy to demonstrate histologically 31. Lipids are present in _____ may be fixed by
because they dissolve in solvent s used for staining in paraffin sections by exposing the
paraffin processing and to a lesser degree in sections to an emulsion of linoleic acid and
celloidin processing. lecithin in 70% ethylene glycol.
- False, lipids are hard to demonstrate - Fat embolism, Fatty Liver and Atheroma
histologically.
32. Lecithin in 70% ethylene glycol must be set
22. They are required in order to stain for lipids. in what temperature? How about the number
- Frozen sections of days?
- 56°C, 3 days
23. They are completely removed in properly
cleared and paraffin infiltrated blocks. 33. Fat tissues are treated with 2% chromic acid
- Triglycerides at 4°C for 24 hours followed by 24 hours in
_____________ with appropriate rinsing
24. Best demonstrated on cryostat sections of between solutions.
fresh unfixed tissue since there is no really - 5% Sodium bicarbonate
good fixative available.
- Lipids 34. _______ and ________ will be lost during
routine dehydration and embedding unless
25. This preserves those lipids that are already they are treated with potassium dichromate
more or less firmly bound to proteins (such or osmic acid, which are the only agents that
as lipofuscins and granules of leukocytes). truly fix lipids.
- Formalin - Phospholipids, neutral fats

26. These are the breakdown products within the 35. Formol-calcium is the fixative of choice for
cells from oxidation of lipids and lipid histochemistry, and is prepared by
lipoproteins. adding how many percent of calcium acetate
- Lipochrome to 10% formalin.
- 2%
27. These are PAS-positive and variably acid
fast. 36. These are used in lieu of the usual
- Lipofuscins dehydration and embedding process.
- Polyethylene glycols (Carbowaxes)
28. Lipofuscins are stained by what staining
technique? 37. Suitable for cryostat sections, and should be
- Ziehl-Neelsen mounted on chrome-gelatin coated slides.
 CHAPTER 19:
STAINING OF LIPIDS
- Formol-Calcium Fixed Tissue
48. It is used to demonstrate the presence of fat
38. Common methods of choice for or lipids in fresh, frozen tissue sections.
demonstrating lipids in tissue sections. - Oil Red 0
- Histochemical techniques 49. It is a fat-soluble diazo dye and is classified
as one of the Sudan dyes which have been in
39. Property of tissues to be stained with fat or use since the late 1800s.
oil-soluble dyes, regardless of the type of - Oil Red 0
dye used, due to their essential lipid nature. 50. It is an adequate solvent for Oil Red 0 and
- Sudanophilia Sudan Black.
- 70% alcohol
40. Oil soluble dyes are usually divided into the
main groups: 51. Fixative of choice for Sudan Black Method
- Basic Aryl Amines with very low water for Lipids
solubility: - Formaldehyde calcium with post-
- B-Naphthol such as the original diazo chroming
dyes:
52. Section of choice for Sudan Black Method
41. It is the most sensitive lipid stain known. for Lipids
- Sudan Black B - Unfixed Cryostat Sections preferred, or
frozen sections post-fixed in formol-
42. These are group of lipid soluble solvent dyes calcium
often called lysochromes.
- Sudan Dyes 53. Results for Sudan Black Method for Lipids
- Lipids: Blue black
43. First dye to be introduced in 1896. - Nuclei: Red
- Sudan III
54. Fixative of choice for Sudan IV (Scharlach
44. Sudan III is followed by what dye in the R) Stain for Lipids
year 1901? - 10% Formalin
- Sudan IV
55. Sections of Choice for Sudan IV (Scharlach
45. It is predominantly used for staining R) Stain for Lipids
triglycerides in animal tissues (frozen - Frozen Sections
sections).
- Sudan III 56. Results for Sudan IV (Scharlach R) Stain for
Lipids
46. It stains phospholipids as well as neutral - Lipids; Red
fats. - Nuclei: Blue/Black
- Sudan Black B
57. It is most commonly used stain producing.a
47. For frozen sections, cut tissues about rapid and permanent coloration of lipid.
_______ micra thick are usually stained with - Scharlach R (Sudan IV)
Scharlach R or with Oil Red 0, which stains
neutral fats and lipofuscin well. 58. It is closely related to Sudan dyes and was
- 15 micra thick introduced in 1926 by French.
 CHAPTER 19:
STAINING OF LIPIDS
- Oil Red 0 - Fats: Black

59. Oil Red 0 is popularized by ________ and 69. It is a dye capable of differentiating two
__________ who advocated its use as a 50 lipid classes simultaneously by the action of
to 60% fresh aqueous dilution of a saturated its two components.
99% isopropanol stock solution. - Nile blue sulfate

60. Oil Red 0 can stain what? 70. It dissolves in Neutral lipids.
- Neutral fats - Red oxazone
- Lipofuschin
71. It is basic and reacts with phospholipids and
61. Fixative of choice for Oil Red 0 Method in free fatty acids.
Dextrin. - Blue oxazone
- Fresh frozen or frozen sections post-
fixed in neutral buffered formalin 72. Nile blue sulfate can be used as a
preliminary indicator of the type of lipid
62. Sections of choice for Oil Red 0 Method in present in the tissue section.
Dextrin. - True
- 5 m sections mount on slides, air dry
73. It involves chemical reaction with specific
63. Results for Oil Red 0 in Dextrin groups, radicals or bonds in the lipid
- Lipid: Red molecule.
- Nuclei: Blue - Histochemical methods

64. It is not a dye but is an unstable oxide which 74. It is based on the observation that free fatty
is reduced to a permanent black substance acids bind heavy metal ions such as copper
by unsaturated fats and fatty acids. to form soaps which can then be stained
- Osmium tetroxide (Osmic Acid) with Weigert’s lithium hematoxylin,
dimethylaminobenzidine rhodamine, or
65. Used as a fixative for electron microscopy rubeanic acid.
and in histochemistry, and for demonstration - Free fatty acids
of unsaturated fats with the disadvantage
that other substances may also be stained 75. Most of earlier methods for demonstrating
simultaneously. cholesterol were ineffective unless
- Osmium tetroxide (Osmic Acid) cholesterol had been oxidized, either
chemically with ferric salts or by long
66. Fixative of choice for Osmic Acid Stain for exposure to atmospheric oxygen.
Fat - True
- 10% formalin
76. The sulfate esters of cerebrosides are
67. Section of choice for Osmic Acid Stain for generally deposited in brain and other
Fat organs of patients with sulfatide storage
- Cryostat Section disease known as _____________.
- Metachromic leukodystrophy.
68. Results of Osmic Stain for Fat
- Nuclei: Yellow-orange
 CHAPTER 19:
STAINING OF LIPIDS
77. This staining technique is capable of
staining cerebrosides and related lipids.
- Periodic Acid Schiff (PAS) Method

78. It is designed to stain mucopolysaccharides

and can be distinguished form glycogen by
removal of diastase.
- PAS Method

79. _______ may have significant ganglioside

storage by giving rise to cells suggestive of
gangliosides, but storage may not be obvious
particularly in subtypes without mental
retardation.
- Neurons

80. The stored gangliosides are _______,

________, and ___________.
- PAS (+)
- Sudanophilic (+)
- Luxol Fast Blue (+)

81. Gangliosides present in storage diseases like

_________ and _________ are stained with
conventional PAS method.
- Tay-Sach’s Disease, Gm1
Gangliosidosis

82. A modified PAS method reduces the

concentration of the oxidizing agent
(periodate) from ____ to ______ to stain
sialo-groups that are oxidized more rapidly
than other sugar glycoside.
- 1 to 0.01%