Functions of human platelets. What function does the platelet perform?

Platelets are one of the main components of human blood. Experts recommend to maintain their level in the norm, otherwise the risk of fatal diseases increases. That is why it is so important to know what function the platelets perform.

Basic concepts

Platelets are rounded blood elements that participate in the normalization of hemostasis. The structure of the cells is microscopic, they do not have a nucleus. Their diameter is only about 3 μm. They are formed from megakaryocytes in the bone marrow. In the bloodstream these elements last from 5 to 11 days. Then they are destroyed in the spleen and liver.

At rest, platelets have the shape of a rounded disc. At the time of activation, they swell and become like a sphere. Since the main functions of platelets in the blood are reduced to the protection of blood vessels, with a cut they form specific outgrowths, called pseudopodia. With the help of these projections, the corpuscles are attached to each other, that is, they pass to the aggregation stage. The cells then adhere to the damaged portion of the vessel. This ability is called adhesion. It is noteworthy that platelets are able to throw dozens of useful microcomponents into the blood, such as enzymes, serotonin, adenosine diphosphate, fibrinogen and others. This distinguishes them from other red bodies.

The main function of platelets

As is known, these blood cells take an active part in the process of clotting, that is, in hemostasis. This is the main function of platelets. For the human body, this process is one of the most important. It helps to prevent significant blood loss during a serious injury.

Thanks to this function of human platelets, the walls of the vessels become stronger. Taurus in a short time clog the site of damage. In fact, these blood cells play the role of primary vascular jams. Clotting occurs as a result of the interaction of enzymes, proteins and about 40 more components. This is a very complex biological mechanism in which platelets, prothrombin and fibrinogen play the main role. The interaction of these elements occurs in the blood plasma.

Auxiliary functions of platelets

In addition to the protective properties, these red plates also have one more useful ability. It is in the endothelial nutrition of the human circulatory system. Thanks to this function of platelets, the vessels receive vital microelements that help normalize the flow of red bodies and the overall work of internal organs. From this property depends largely on the degree of protection of the body (immunity).

Also, blood cells actively participate in regeneration, that is, in the healing of tissues after injury. This effect is achieved by an accelerated process of division and release from the vessels. In other words, platelets perform the function of plugging the entire site of damage. Moreover, they contribute to the accelerated growth of the affected cells. This process is understood as the division of polypeptide molecules. During the activation of platelets, the growth of fibroblasts also occurs. Also at this moment, microcomponents are created that are responsible for the transformation of cells and the restoration of insulin levels.

Indicators of the norm

In humans, platelets should always be within the generally accepted limits. In the general analysis, values per 1 liter of blood are given. The specificity of the entry is as follows: x10 ⁹ / l. The norm in an adult is the number of platelets in the range of 200 to 400 units. At teenagers from 15 till 18 years these indicators - 180-420. Children under 15 years of age range from 150 to 450 units. In newborns, the minimum threshold is 100, and the maximum threshold is 400.

It is worth noting that in women, the limits of platelets can be just below the above standards. It depends on the physiological characteristics and the level of hormones. In addition, at the moment of menstruation, the minimum threshold of platelets falls sharply due to loss of blood. A similar situation is observed in pregnant women, when the level of regenerating bodies can decrease severalfold. This is due to the increase in the volume of fluid in the blood. Therefore, the analysis shows a decrease in the number of all microcomponents. It is important to understand that the numerical values of platelets are not the main thing. With the results of the analysis, in any case, you need to see a doctor to make additional studies to determine the effectiveness of their actions. This procedure is called a coagulogram.

Deviations and their causes

If the blood test showed that there is a deficiency or an excess of platelets in the body, it is necessary to urgently undergo additional medical examination. This is the first alarm sign that signals the development of a serious illness.

Since blood platelets are indispensable and vital, any abnormality affects the general condition of the body. Reducing the number of corpuscles increases the risk of long healing, even with minimal damage. In other words, blood coagulability is minimized. When the level is raised, the protective functions of the platelets are activated. In this case, large junctions that violate the blood flow will form in the vessels. As a result, there is a risk of developing blood clots. Sharp deviations from medical norms may indicate an initial stage of an oncological disease.

To prevent and maintain platelet levels, doctors recommend proper nutrition. In the diet, there should always be plenty of vitamin B12 and folic acid.

Decreased platelet function

This condition occurs during a significant decrease in the number of regenerating bodies in the blood. As a result of this decline, internal organs become vulnerable to infection. This detrimental effect primarily on the liver and thyroid gland. The reasons for reducing the number of platelets and their functionality can be such diseases as rubella, leukemia, measles. The most terrible of them is a cancerous tumor. In addition, a decrease in the level is observed in patients after chemotherapy, as well as in case of an overdose of aspirin and during dehydration. Some strong antibiotics can adversely affect the growth of blood cells.

Reducing the level of platelets requires compulsory treatment. First of all, the doctor should prescribe pharmacological preparations. And already on the second place are diet and prevention of herbs. Folk methods are powerless here, and delaying treatment can lead to imminent consequences. It is important during the prophylaxis not to take medications that dilute the blood, for example analgesics, "Aspirin", sulfonamide group.

Platelet excess

An increase in the level of regenerating cells indicates an oncological disease. In addition, this affects the auxiliary functions of platelets. An excess of corpuscles is also possible with sepsis or after an operation to remove the spleen. A special case may be severe internal bleeding.
As a result of a rapid increase in platelets in the vessels formed embolus. Such a problem requires an immediate solution. It should be noted that self-treatment will not yield any results. Only pharmacological therapy will help here. Of the most common drugs can be identified "Pirabutol" and "Aspirin". It is also important to exclude any body overload.

Probable diseases

When the level of platelets is lowered, the risk of developing aplastic anemia, Verlhofe's and Gaucher's disease, and cytopenic purpura is high.

With an increase in the number of red plates in the blood, there is a possibility of dengue fever and hemolytic syndrome. But first of all it is necessary to be checked up on onkozabolevanija.

Violation of the function of platelets to aggregation and adhesion entails the syndromes of Bernard-Soulier, von Willebrand, Pudlac, Scott.

If the metabolism of red bodies fails, atherosclerosis, ischemia of the heart, cerebrovascular and arterial diseases, malaria, asthma, cancer are observed.