Astrocytes are demonstrated by which procedure?

• A. Cajal
• B. Bodian
• C. Weil
• D. Nissl

Answer: (A)

Demonstrating astrocytes relies on a silver impregnation technique that stains whole cells and their fine processes, allowing visualization of the star-shaped glial morphology and the extensive network they form in the neuropil. This is the Golgi-Cajal staining method. It randomly impregnates a small subset of cells with silver, so you can see not only cell bodies but also the delicate, branched processes that define astrocytes and their interactions with neurons and blood vessels. Other stains focus on different neuronal components—Nissl highlights neuronal cell bodies and Nissl substance, Bodian emphasizes axons, and Weil highlights myelin—so they don’t reveal astrocyte morphology as clearly.