Cresyl echt violet demonstrates which tissue component?

• A. Nissl substance
• B. Myelin
• C. Astrocytes
• D. Glial fibers

Answer: (A)

Cresyl violet is a basic dye that binds strongly to nucleic acids, highlighting the rough endoplasmic reticulum within neurons. This ribosome-rich area is called the Nissl substance, so staining with Cresyl violet makes the Nissl bodies appear as dark purple/purple-blue granules inside the neuronal cell body. This differentiation helps identify neurons and assess neuronal health, since Nissl substance reflects the distribution of rough ER and ribosomes involved in protein synthesis. Myelin, astrocytes, and glial fibers aren’t specifically highlighted by this stain because myelin is lipid-rich and many glial structures lack dense rough ER, so they don’t produce the same dark Nissl staining.