Which control slide demonstrates lipid content in the liver using a lipid-specific stain?

• A. Oil Red O
• B. PAS glycogen
• C. Hematoxylin & Eosin
• D. Verhoeff's Van Gieson

Answer: (A)

Demonstrating fat content in liver relies on a stain that specifically binds lipids and stays where the lipids are, which typically means using frozen tissue because standard paraffin processing removes lipids. Oil Red O fits this need perfectly: it is a lipid-soluble dye that stains neutral lipids and triglycerides bright red, making lipid droplets within hepatocytes easy to visualize on frozen sections. This targeted labeling is essential for identifying hepatic steatosis. In contrast, PAS glycogen highlights carbohydrates like glycogen, Hematoxylin & Eosin provides general tissue morphology, and Verhoeff's Van Gieson emphasizes elastic fibers and connective tissue—none of these selectively marks lipids. So Oil Red O is the best choice for showing lipid content in the liver.