Neurons are one of the most important types of cells in our body, since they allow the transmission of information between its different parts through the nervous system. Through them, a series of bioelectric impulses are generated and transmitted that allow us to carry out each of the actions we carry out, both voluntarily and involuntarily, and whether we refer to physical behaviors or cognitive processes. or emotional.
But neurons are not homogeneous masses: if we focus on their structure we can distinguish different elements or parts. One of the most important is the soma of the neuron, or perikaryon to which this article is dedicated.
The central part of the neuron: The soma or perikaryon
The central and most important element of the cell, in which the nucleus is located and from which its other parts are derived, as extensions of the first: dendrites and axon, is known as the soma or perikaryon. The shape of the soma, as well as its position in relation to the rest of its components of the same neuron, can vary greatly depending on the type of neuron we are talking about (although it is generally rounded and large).
The somata of neurons make up what we call gray matter, linked to the processing of nervous information. In fact, different brain structures of great importance are mainly made up of gray matter, such as the cortex itself, the basal ganglia, the thalamus or the hypothalamus.
Within the soma or perikaryon we can find a large number of elements, all of them of great importance, that participate in the proper functioning of the cell and its maintenance. The main among them are the following.
1. Core
The main and most important element of the soma is the nucleus, which contains the genetic instructions that govern the formation, growth, functioning and death of the neuron, that is, the DNA. Within the nucleus or around it can be found the nucleolus, which generates RNA transcription which will end up generating the ribosomes present in the cell.
2. Cytoplasm
The cytoplasm is the liquid medium in which the nucleus and the rest of the elements of the soma are found. actively participating in cellular metabolism and facilitating their movement It is limited by the cytoskeleton of the neuron membrane.
3. Cytoskeleton
This item made up of different types of filaments and tubules They contribute to providing a structure and shape to the perikaryon and also participate in the migration and movement of the different components of the soma.
4. Nissl bodies
Clusters of rough endoplasmic reticulum present mainly in the soma (although they can also be observed in the dendrites) and containing a large number of ribosomes, which participate in the creation of proteins and neurotransmitters. In addition, they are a fundamental part of the perikaryon, since if the cell is damaged (not only in the soma but also, for example, in the axon), these elements will be the ones that contribute to its regeneration, dissolving and sacrificing themselves to maintain the functioning of the neuron. (in a process known as chromatolysis).
Element of great importance for the functioning of the neuron, the Golgi apparatus is a large organelle in which proteins generated by Nissl bodies are temporarily stored incorporating other elements in such a way that they can be packaged into macromolecules that can be sent through the neuron to the nerve terminals.
6. Smooth endoplasmic reticulum
Network of interconnected tubules whose main function is to serve as an assembly point for many substances secreted by the rest of the elements It also participates in the synthesis of lipids and elements related to the neuron membrane. The aforementioned Golgi apparatus is, in fact, smooth endoplasmic reticulum.
7. Lysosomes
Set of elements present in the cytoplasm whose main function is to degrade intracellular material facilitating the functioning of the soma by eliminating harmful remains.
8. Ribosomes
Present in some of the previous structures but also freely located in the cytoplasm, Ribosomes are macromolecules made up of ribosomal RNA and some proteins which are responsible for protein synthesis. Technically, they are the elements that carry out the expression of the genetic information present in the nucleus, through said synthesis.
9. Mitochondria
Fundamental elements of the cell whose main function is to provide it with energy and keep it alive carrying out cellular respiration and synthesizing ATP (an element that cells use as fuel).
Its function
The soma or perikaryon plays a fundamental role: it is the part of the neuron that governs the functioning and keeps this biological unit alive, finding the nucleus of the cell (in which the genetic instructions present in DNA are found) in it. It is responsible for producing and maintaining a sufficient level of energy so that the cell can continue functioning. It also contains elements that form the cytoskeleton of the cell, as well as some elements that repair it from possible damage, such as Nissl bodies.
Perhaps the most important role of the soma is the fact that it carries out the synthesis of most of the proteins found in the neuron, including those that will form part or They will initiate the synthesis of most neurotransmitters
Finally, it is from it that the extensions that will receive and send nervous information are derived.
This is the part of the neuron that, also, allows the processing of nervous information and its reaction to it being the somas of neurons an important part when it comes to explaining how human beings function and govern their behavior.
