The neuronal cell body consists of a large nucleus with a ruffled nuclear membrane, sparse chromatin, and a conspicuous nucleolus, in which the cytoplasm is composed of Nysted granules, i.e., basophilic granules that are representative of the rough endoplasmic reticulum and that give rise to specific patchy basophilic manifestations in many neurons. Nissen granules can be visualized with a number of stains such as neutral red, methylene blue, toluidine blue, and methyl violet, and the variability of staining, pH, and time of differentiation allows some stains to highlight both the Nissen material alone and the nucleus and glia of the neuron. Nissl bodies, or Nissl vesicles, are small, triangular or oval-shaped masses distributed in the cytoplasm of nerve cells that can be stained a purplish-blue color by basic dyes such as sulphur cordyceps, methylene blue, toluidine blue, and tar violet; Nissl bodies are found in all types of nerve cells but often differ in shape, number, and location, and they are also found in dendrites but not in axons and axon thalamus of the encapsulated body . Nichols' bodies change due to changes in physiological status. Nichols' bodies are an important site for synthesizing protein synthesis within neurons, and when neurons are stimulated, the number of Nichols' bodies within the envelope decreases significantly.

The main features of Nissl Staining Kit (Nissl Stain, Methyl Violet Method) are easy operation, stable staining, short differentiation time, and wide range of application, which can be used for staining of Nissl substances, neurons and so on in paraffin tissue sections.The presence and disappearance of Nissl bodies is an important indicator of whether the nerve cells are damaged or not, and when encephalitis, cerebral ischemia, and axon responses occur, Nissl bodies will dissolve or even disappear .