{{short description|Rough endoplasmic reticulum structure found in mitochondria}} [[File:Nissl bodies in neurons of the spinal cord.jpg|thumb|[[Photomicrograph]] of Nissl bodies (two are indicated by arrows) in the [[cytoplasm]] of motor neurons in the anterior horn of the [[spinal cord]]; [[cresyl violet]] stain (purple) along with a [[luxol fast blue]] stain for [[myelin]]. Scale bar = 30 [[micron|microns]] (0.03mm).]] [[Image:Gray626.png|thumb|200px|Drawing of a motor neuron from the ventral horn of the medulla spinals of a rabbit. The angular and spindle-shaped Nissl bodies in the cytoplasm are well shown.]]
In [[cellular neuroscience]], '''Nissl bodies''' (also called '''Nissl granules''', '''Nissl substance''' or '''tigroid substance''') are discrete granular structures in [[neuron]]s that consist of rough [[endoplasmic reticulum]], a collection of parallel, membrane-bound [[cisternae]] studded with [[ribosomes]] on the [[cytosol]]ic surface of the membranes.<ref name="Junqueira">{{cite book |last1=Junqueira|first1=L. Carlos |last2=Carniero|first2=Jose |last3=Kelley|first3=Robert O. | name-list-style = vanc |title=Basic Histology| publisher=Appleton & Lange|date=1995|isbn=0-8385-0567-8}}</ref> Nissl bodies were named after [[Franz Nissl]], a German [[neuropathologist]] who invented the [[staining]] method bearing his name ([[Nissl stain|Nissl staining]]).<ref name="Thompson2000">{{cite book|author=Richard H. Thompson|title=The Brain: A Neuroscience Primer|url=https://books.google.com/books?id=PPAaU1cQUPsC&pg=PA35|access-date=4 January 2013|date=29 March 2000|publisher=Macmillan|isbn=978-0-7167-3226-6|pages=35–}}</ref><ref name="Da Mota Gomes">{{cite journal | author = Da Mota Gomes M | title = Franz Nissl (1860-1919), noted neuropsychiatrist and neuropathologist, staining the neuron, but not limiting it | journal = Dementia & Neuropsychologia | volume = 13 | issue = 3 | pages = 352-355 | year = 2019 | doi=10.1590/1980-57642018dn13-030014| pmc = 6753910 }}</ref> The term "Nissl bodies" generally refers to discrete clumps of rough endoplasmic reticulum and free ribosomes in nerve cells. Masses of rough endoplasmic reticulum also occur in some non-neuronal cells, where they are referred to as [[basophilic]] bodies,<ref name="Junqueira"/> or chromophilic substance.<ref name="Fawcett">{{cite book |last=Fawcett|first=Don W. |title=The Cell: Its Organelles and Inclusions| publisher=W.B. Saunders Company|date=1966|isbn=0-7216-3585-7}}</ref> While these organelles differ in some ways from Nissl bodies in neurons,<ref name="PetersPalayWebster">{{cite book |last1=Peters|first1=Alan |last2=Palay|first2=Sanford L.|last3=Webster|first3=Henry deF. | name-list-style = vanc |title=The Fine Structure of the Nervous System| publisher=Oxford University Press|date=1991|isbn=0-19-506571-9}}</ref> large amounts of rough endoplasmic reticulum are generally linked to the copious production of proteins.<ref name="Junqueira"/>
==Staining== "Nissl stains" refers to various basic dyes that selectively label negatively charged molecules such as [[DNA]] and [[RNA]]. Because ribosomes are rich in [[ribosomal RNA]], they are strongly [[basophilic]] ("base-loving"). The dense accumulation of membrane-bound and free ribosomes in Nissl bodies results in their intense coloration by Nissl stains, allowing them to be seen with a light [[microscope]].<ref name="Junqueira"/>
==Size and distribution== Nissl bodies occur in the [[soma (biology)|somata]] and [[dendrites]] of neurons, though not in the [[axon]] or [[axon hillock]].<ref name="Kühnel2003">{{cite book|author=Wolfgang Kühnel|title=Color Atlas of Cytology, Histology, and Microscopic Anatomy|url=https://books.google.com/books?id=wUFAGmVN_aMC&pg=PA182|access-date=4 January 2013|year=2003|publisher=Thieme|isbn=978-3-13-562404-4|pages=182–}}</ref> They vary in size, shape, and intracellular location; they are most conspicuous in the [[motor neurons]] of the [[spinal cord]] and [[brainstem]], where they appear as large, blocky assemblies.<ref name="PetersPalayWebster"/> In other neurons, they may be smaller, and in some (such as the granule neurons of the [[cerebellum|cerebellar]] cortex) very little rough endoplasmic reticulum is present.<ref name="PetersPalayWebster"/> The pattern of coloration with Nissl stains once was used to classify neurons.<ref name="PetersPalayWebster"/> For various reasons, this practice has largely ceased, but specific neuronal types do manifest characteristic types of Nissl bodies.<ref name="PetersPalayWebster"/>
==Functional role== The functions of Nissl bodies are thought to be the same as those of the rough endoplasmic reticulum in general, primarily the synthesis and segregation of proteins.<ref name="Junqueira" /><ref name="Thompson2000" /> Similar to the ergastoplasm of [[gland|glandular]] cells, Nissl bodies are the main site of protein synthesis in the neuronal [[cytoplasm]].<ref name="PetersPalayWebster" /> The [[ultrastructure]] of Nissl bodies suggests they are primarily concerned with the synthesis of proteins for intracellular use.<ref name="HerdegenDelgado-Garcia2005">{{cite book|author1=T. Herdegen|author2=J. Delgado-Garcia|title=Brain Damage and Repair: From Molecular Research to Clinical Therapy|url=https://books.google.com/books?id=Yz89owzM91kC&pg=PA37|access-date=4 January 2013|date=25 May 2005|publisher=Springer|isbn=978-1-4020-1892-3|pages=37–}}</ref> ==Pathology== Nissl bodies show changes under various physiological conditions and in [[pathological]] conditions such as [[axonotmesis]], during which they may dissolve and largely disappear ([[chromatolysis]]). If the neuron is successful in repairing the damage, the Nissl bodies gradually reappear and return to their characteristic distribution within the cell.<ref name="PetersPalayWebster"/>
==References== {{reflist}}
==External links== *{{Commonscatinline|Nissl stain}} *{{MeshName|Nissl+Bodies}} *{{BUHistology|04103loa}} - "Nervous Tissue and Neuromuscular Junction: spinal cord, cell bodies of anterior horn cells" *[http://www.lab.anhb.uwa.edu.au/mb140/CorePages/Nervous/Nervous.htm Histology at anhb.uwa.edu.au] *[http://www.hms.harvard.edu/societies/castle/Room166/bodyblock/histology/ Tissues containing Nissl bodies at harvard.edu]
{{Nervous tissue}}
[[Category:Nervous tissue cells]]