Nissl clods

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As Nissl bodies , Nissl substance , Nissl granules or tigroid be in neuroanatomy and neuropathology called cellular structures using to basic blue dyes, purple or metachromatically can stain and almost all nerve cells are found, depending on the cell type as fine-grained or coarse lumpy fields in the soma ( perikaryon ) and in dendritic areas close to the soman.

Staining method

The name Nissl-Schollen refers to the first person to describe the staining method , the Heidelberg psychiatrist Franz Nissl (1860–1919), who used the staining technique named after him on nerve cells. However, other cells with a high protein turnover can also be stained in this way.

Morphological differentiation depending on the neuronal cell type

In motor neurons, the Nissl substance shows a coarse, coarse and lumpy expression, while it is z. B. in nerve cells of the sensitive dorsal root ganglia appears as fine dust in the part of their protoplasm near the cell nucleus .

Histochemistry

The degree to which Nissl clods can be stained goes hand in hand with the rate of protein synthesis in a cell, especially the nerve cell. This protein production is highest near the cell nucleus and relies on ribonucleic acid (RNA). Protein synthesis takes place in the ergastoplasm . The ribosome-occupied part of the rough endoplasmic reticulum (rER) contains RNA. This explains the coloring of the Nissl clods with the help of basic dyes.

In a nerve cell, the synthesis of proteins takes place predominantly in the area of ​​the perikaryon, hardly in the nerve cell processes and not in the area of ​​the neurite . The neurite is free of Nissl clods, already its cone of origin . If there is no corresponding color in the histological section, the point of departure of the axon can be recognized by light microscopy . This fact can be explained by the assumption that the proteins synthesized in the perikaryon are mainly consumed in the axon (neurite) during work and are regenerated with the participation of the cell nucleus. Hence there is a constant influx of plasma into the neurites. The continuous flow of axoplasma is evidenced by artificial back pressure within the neurite and by isotope labeling. The dendrites contain Nissl substance only to a lesser extent in the sections near the perikaryon.

Formation and distribution of the Nissl clods can show characteristic patterns in different types of nerve cells and also change depending on activity, including disease-related.

Equivalent images

Nissl called the representation of the clods colored under the same conditions as equivalent images. He considered these structures to be regular changes to preformed structures. It was not until 1955 that the role of the rough endoplasmic reticulum (rER) for Nissl substance was recognized. However, it turned out that the Nissl bodies themselves do not have any solid structures; they are not tied to the existence of the rER, but also the product of the staining of free ribosomes. Therefore, Nissl granules can also be viewed as freely shapable or simply as chromatophilic substances . Centrifugation removes them from the perikaryon and shifts them more towards the cell edge. In this respect, the question arises as to whether the Nissl substance in the current representations is possibly to be understood as a mere cast image of the rER. As such an “equivalent image”, it would show gaps in the endoplasmic network. However, the neurofibrils are also to be considered here as possible fixed endoplasmic components of a nerve cell, which may be suitable for influencing the light microscopic structure of the Nissl clods. It is not clear why the Nissl substance differs in motor and sensory neurons.

Pathological findings

Under pathological conditions, the Nissl substance can show changes; it can be used to chromatolysis come.

Individual evidence

  1. ↑ Renate Lüllmann-Rauch: Pocket textbook histology . 3. Edition. Georg Thieme, Stuttgart 2009, ISBN 978-3-13-129243-8 , p. 167 f.
  2. ↑ a b c d e f Nissl substance . In: Helmut Ferner : Anatomy of the nervous system and the human sensory organs. 2nd Edition. Reinhardt, Munich 1964, pp. 22-29.
  3. ↑ a b c d Norbert Boss (Ed.): Roche Lexicon Medicine . 2nd Edition. Hoffmann-La Roche AG and Urban & Schwarzenberg, Munich 1987, ISBN 3-541-13191-8 ; (a) on Lex.-Lemma “Nissl-Schollen”: p. 1244; (b) to Lex.-Lemma “Ergastoplasma”: p. 519; (c) to Lex. Lemma “Ribosomes”: p. 1486; (d) on Lex.-Lemma "Nissl-Schollen": p. 1244, cf. Gesundheit.de/roche
  4. ↑ a b Max Watzka: Short textbook on histology and microscopic human anatomy . FK Schattauer, Stuttgart 1964; (a) on district “Ergastoplasma”: p. 3, 64; (b) on district “Nissl-Schollen”: p. 64 f.
  5. ^ Alfred Benninghoff : Macroscopic and microscopic anatomy of humans . Volume 3: Nervous System, Skin and Sensory Organs . Verlag Urban & Schwarzenberg, 1985, ISBN 3-541-00264-6 , p. 11.
  6. ↑ Alfred Benninghoff , Kurt Goerttler : Textbook of Human Anatomy. Shown with preference given to functional relationships. Volume 3: Nervous System, Skin and Sensory Organs. 7th edition. Urban & Schwarzenberg, Munich 1964; (a) on tax authority “Nerve cell as a trophic unit”: p. 74 f .; (b) Re. “Equivalent images”: p. 76.
  7. ↑ P. Weiss: Damming of axoplasm in constricted nerve. A sign of perpetual growth in nerve fibers . In: Antom. Rec. , 88, 1944, p. 464.
  8. ↑ Benninghoff: Macroscopic and microscopic anatomy of humans, Volume 3: Nervous system, skin and sensory organs . Verlag Urban & Schwarzenberg, 1985, ISBN 3-541-00264-6 , p. 11.
  9. ↑ Palay & Palade: J. Biophys. Biochem. Cytology. I, 55, 1955.