This method is used for the detection of Nissl bodies in the cytoplasm of neurons on formalin-fixed, paraffin embedded tissue sections, as well as frozen sections.The Nissl body is a chromophil substance in the form of granules found in the cell bodies and dendrites of neurons, but is absent from axons. Nissl bodies are involved with protein synthesis and metabolism; their aspect vary with physiological and pathological conditions. This stain is one of the most commonly used for identifying basic neuronal structures in the brain or the spinal cord.