This fluid is essential for the nervous system to function properly.
However, what not everyone knows is that both the brain and the spinal cord are kept in good working order thanks to the existence of a liquid that, as with the skull, gives it protection and also offers it nutrients.
This substance is the cerebrospinal fluid, a substance that plays a very important role in the health of the nervous system and prevents our most precious organ, the brain, from being seriously damaged by different factors. Let’s see in more depth what this liquid is about.
- Recommended article: “Human brain: its parts and main functions”
What is cerebrospinal fluid?
Cerebrospinal fluid, also called cerebrospinal fluid, is a substance found in the nervous system , both in the brain and in the spinal cord. This liquid acquires great importance for the correct functioning of the nervous system, since it offers protection, nutrition, maintains intracranial pressure, in addition to preventing the brain from being damaged by its own weight.
Cerebrospinal fluid is found especially in the subarachnoid space, that is, between the arachnoid meninges and pia mater, and also in the cerebral ventricles. Its composition is similar to that of blood plasma, since it is derived from it.
Normally, and due to its composition, it has no color, however, its hue can change if it is no longer healthy, especially if there has been some type of infection or hemorrhage in the brain.
production cycle
The course of cerebrospinal fluid begins at the choroid plexuses . These structures are found in the cerebral lateral ventricles and their main function is to elaborate this substance. The synthesis of cerebrospinal fluid occurs constantly, since it is of fundamental importance to maintain an adequate amount of this substance in the nervous system.
Once the liquid has been manufactured, it starts from the lateral ventricles until it reaches the third ventricle and, subsequently, it reaches the fourth through the Silvio aqueduct. It is in the fourth ventricle that it projects into the subarachnoid space, entering through several holes, specifically the Magendie orifice and the Luschka orifices. These openings are found in the fourth cerebral ventricle and connect the ventricular system with the meningeal system.
The cerebrospinal fluid travels through the subarachnoid space to reach the entire central nervous system, performing different functions along the way. Subsequently, this substance is reabsorbed through the arachnoid granulations and through the veins, through which it is recycled and enters the bloodstream. This whole process takes about three hours.
Nutritional composition
Cerebrospinal fluid is an aqueous solution that is similar in composition to blood plasma.
It differs from plasma by the fact that it has a very small amount of protein, in addition to having other types of electrolytes, although with the same sodium levels. Among the components present in the cerebrospinal fluid are vitamins, especially type B, leukocytes, choline, amino acids and nucleic acid.
The main protein that can be found in the cerebrospinal fluid is albumin, along with other protein components such as prealbumin, alpha-2-macroglobulin, and transferrin. However, the most common component is glucose, found in percentages between 50% and 80%.
Principal functions
The cerebrospinal fluid is a substance of vital importance, since it fulfills a series of functions that guarantee that the nervous system works in the most optimal way. Below we will look at the top five.
1. Buoyancy
The human brain has a mass that ranges between 1,400 and 1,500 grams . However, its relative weight is between 25 and 50 grams thanks to the fact that it floats in the cerebrospinal fluid.
This function is very important, since it is what prevents the lower part of the brain from being damaged by its own weight, in addition to preventing cerebral blood flow from being affected.
2. Protection
Cerebrospinal fluid protects the brain and spinal cord from external shocks, acting as a shock absorber.
3. Cranial pressure
Depending on the amount of fluid in the skull, there will be more or less pressure on the brain .
Thus, as long as it is maintained at optimal levels, this substance can play a very important role in preventing ischemia, reducing cerebral pressure and facilitating blood perfusion.
4. Homeostasis and nutrition
One of the great functions that this liquid has is to ensure that the nervous system is well nourished . Thus, it regulates the levels of hormones, nutrients and pH in the brain to prevent deficits and organic failures at the nerve level.
5. Waste disposal
Last but not least, the cerebrospinal fluid plays a fundamental role in ‘cleaning up’ the nervous system .
Our brain is constantly working, which also means that it is constantly producing waste. If these residues are not properly eliminated, they can accumulate and subsequently poison the nervous system.
The cerebrospinal fluid is responsible for capturing these substances so that they can be properly excreted and thus prevent the nervous system from being damaged.
Associated pathologies
In the same way that a healthy cerebrospinal fluid is very important to maintain good organic conditions, its poor synthesis or infections in it imply health problems of different severity. Next we will see four health problems related to this substance.
The first two disorders are directly related to a poor production of cerebrospinal fluid, while the last two are not due to an excess or deficit of this substance, but the fluid does play an important role when diagnosing these conditions. diseases.
1. Hydrocephalus
Hydrocephalus implies that there is an excess of cerebrospinal fluid inside the skull , which leads to an increase in physical pressure on the brain. The causes behind the appearance of this medical condition can be several, such as tumors, infections or trauma, as well as obstructions in orifices such as Magendie’s. There are cases of hydrocephalus that are congenital, already arising from birth and whose cause is genetic.
People with hydrocephalus suffer from headaches, cognitive decline, coordination problems, double vision, dizziness, and vomiting. If it is congenital, special care must be taken and monitoring of how the child develops, since learning may be affected.
Among the treatments available to deal with hydrocephalus is the use of drugs that act on the infection or, if it is due to a tumor or obstruction, surgical intervention.
2. Cranial hypertension and hypotension
The cerebrospinal fluid has the outstanding function of regulating the pressure exerted on the brain . However, if there is too much fluid, cranial hypertension occurs, while if there is too little, we speak of hypotension.
Hypertension is especially harmful, that is, too much pressure on the brain, since it can damage this structure that is so important for the survival of the organism. The gravity can be such that parts of the brain tissue are damaged, killing them.
3. Alzheimer’s disease
Cerebrospinal fluid may contain biomarkers that provide information about brain health . In Alzheimer’s disease, although total amyloid beta (Aβ) does not differ significantly compared to healthy people, lower levels of Aβ42 do occur.
It is believed that this is so because it accumulates in the form of plaques in the brain and, therefore, is dispersed in a smaller quantity in the cerebrospinal fluid.
Tau levels, both total and phosphorylated, are increased in cerebrospinal fluid.
4. Creutzfeldt-Jakob disease
The most widely used biomarker to diagnose Creutzfeldt-Jakob disease (CJD) is the 14-3-3 protein . These types of proteins are responsible for performing functions that have to do with the regulation of cells. If the 14-3-3 protein is found at high levels in a patient with signs of dementia lasting less than two years, it is considered a strong indicator of CJD.
This same protein is increased in patients who have suffered strokes, encephalitis and other problems in which there is extensive damage to the brain.
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