Nissl substance

Interpretation dying cells in the ventral horn of the spinal cord may be distinguished by loss of Nissl substance in the cell bodies, by pyknotic nuclei, and by pink cytoplasm in cells that are early in the degeneration process (see Note 1). 

While neuron-specific enolase (NSE) has been described as a marker of neuronal tumors in reviews and texts, this author finds that it has better uses than this. The shortcoming for neuronal tumors is its propensity to also stain glial tumors, which commonly need to be distinguished from neuronal tumors. 7 Experimental IFIC stains such as Neu-N identify neurons by showing their on-target nuclear features rather than their cytoplasmic or confusing surface features. " 425 cases refractory to immu-nohistochemical stains, electron microscopy positively identifies Nissl substance, neurofilaments, neurosecretory granules, and synapses in neoplastic cells. 

Other organelles include the rough endoplasmic reticulum, the subsurface cisternae, and the mitochondria. As in other cell types, the rough endoplasmic reticulum is the primary site of protein synthesis. In neurons, this granular organelle studded with ribosomes is also known as the Nissl substance, due to its chromophilic nature. It is highly developed in neurons and reflects the active protein synthesis that is constantly occurring in these cells. Few of the proteins synthesized at the Nissl bodies are secreted and the majority of them remain within the cell or are incorporated into the cell membrane. After ribosomal translation, many of the proteins are transported... 

The nuclear membrane is not smooth all the way around the nucleus but is wrinkled or puckered on the side facing the origin of the dendritic tree, the wrinkles vary from a shallow dimple in the surface of the nucleus to a deep and complicated crease with many tributary folds. The irregular depression in the nucleus is stuffed with Nissl substance, forming a prominent basophilic nuclear cap, which both... 

Sections developed with permanent labeling methods (e.g., with DAB) can also be counterstained using, for instance, cresyl violet or aqueous toluidine blue to stain Nissl substance. For permanent stains, the usual mounting medium is one of low viscosity so it gives a thinner adhesive layer of appropriate optical properties (e.g., Permount ). For fluorescence, a corresponding typical fluorescence-free mounting medium is preferred (e.g., VECTASHIELD ). 

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