Phosphotungstic acid hematoxylin is used to stain which components?

• A. Myelin and glial fibers
• B. Neuronal cell bodies
• C. Blood vessels
• D. Dendrites

Answer: (A)

Phosphotungstic acid hematoxylin highlights fibrous neural elements, especially myelin and glial fibers. The stain combines hematoxylin with phosphotungstate to produce a blue-black coloration of lipid-rich myelin sheaths and the filamentous glial processes, making nerve fibers and gliosis stand out against a lighter background. Neuronal cell bodies are not the primary target and are less distinctly stained, while blood vessels and dendrites do not show the characteristic blue-black detail that PTAH affords for myelin and glial fibers.