The concept of dendrite is used to name a protoplasmic extension with ramifications that is part of a nerve cell and allows it to receive stimulation from the outside. Dendrites, therefore, are terminal branches present in neurons that guarantee the reception of nerve impulses that arrive from an axon corresponding to another neuron.
The dendrite, experts say, is the portion of the neuron that receives excitation as a result of stimuli generated by other cells or environments. The axon, for its part, is responsible for distributing said excitation from the dendritic area.
It should be noted that these numerous branched extensions present other smaller extensions known as dendritic spines, which are the sites where the synapse develops.
In case of any disorder in the dendritic spines, problems related to cognition develop. Down syndrome is one of the diseases related to atrophy or poor development of these dendrite extensions.
The dendrites, whose cytoplasm contains mitochondria, microtubules, membranous vesicles, and neurofilaments, have chemoreceptors that react with the neurotransmitters sent by the synaptic vesicles of the presynaptic neurons. This means that the dendrites are essential for the transmission of impulses through the nerve pathway formed by the neurons.
It should be noted that the dictionary of the Royal Spanish Academy (RAE) accepts other uses of the dendrite concept. The term can then be used to refer to the mineral structure that, with an appearance similar to the branches of trees, appears in the cracks and joints of rocks. Another use of the notion is found in engineering, where the dendrite is a metallic crystal that is produced by solidification and whose structure is reminiscent of a many-branched tree.
The role of dendrites in neurodegenerative diseases
Thanks to a study carried out at the University of Pennsylvania, it has been discovered that the work of dendrites is not only restricted to receiving and sending chemical and electrical signals, but that they can also create proteins (previously it was believed that the only area of the cell where could be done was the core).
This would reveal the fundamental role of these nerve extensions in the memory and learning process and make them a fundamental element when it comes to triggering neurodegenerative diseases. This is due to the fact that a minimal error in the coding of the RNA could result in a malformation of proteins that could harm the brain circuits that allow the normal functioning of memory, inevitably affecting it.
This new discovery could be fundamental when studying ways to cure or prevent diseases of this type, such as Alzheimer’s. This disease is a progressive type and a way of recovery for it is not yet known. It is a disease that affects the nerve cells in the different regions of the brain, causing dysfunction in it; such that the individual loses all ability to control their emotions, recognize patterns, coordinate movements and remember things. Within dementias, this is the most common, especially in older people, and is the fourth leading cause of death in adults.
There are also other diseases related to dendrites, many of them exclusively linked to dendritic spines, which we have already discussed in previous paragraphs. Among them are spinal disorders such as diseases in the spine (where deviations are usually the most common), bone problems (where fractures are the most common) or even muscle atrophy or problems of various kinds in any body muscle.
All this would lead us to understand that the role of dendrites is much more essential than previously believed and that it would open new paths for research to counteract the effects of degenerative diseases.