Life expectancy of human and animal erythrocytes

Erythrocytes are called cells, the role of which is the transport of oxygen and carbon dioxide. In humans and mammals, these are denuclearized uniform elements that are formed by the red bone marrow. Performing their function, they acquire new and new damages. Over time, they, unable to recover, mutated and deformed, must be destroyed.

The process of erythrocyte destruction

Because of the natural mechanism of cell aging, the life span of red blood cells is 120 days. This is the average time that cells can perform their function. Although theoretically, the red blood cell can die and immediately after exiting the bone marrow. The reason is mechanical damage, which occurs, for example, during a long march or injury. Then the destruction occurs either in the hematoma, or inside the vessels.

The natural process of destruction, which regulates the life span of red blood cells, occurs in the spleen. Macrophages recognize cells with a small number of receptors, which means that they have long circulating in the blood or have significant damage. Then the element is digested by the macrophage, which separates the heme (iron ion) from the protein part of the hemoglobin. The metal is sent back to the bone marrow, where it is transferred to the fissioning proerythroblast by the feeding cage.

Features of vital activity of human erythrocyte

Theoretically, the life span of human erythrocytes could be infinitely large under certain conditions. First, there should be no mechanical resistance to blood circulation. Secondly, the erythrocytes themselves should not be deformed. However, in the vascular channel of the person, these conditions can not be observed.

When the red blood cells move along the vessels they survive multiple mechanical effects. As a result, the integrity of their membranes is impaired, some surface receptor proteins are damaged. Moreover, the erythrocyte has no nucleus and organelles designed for protein biosynthesis. Hence, the cell can not repair the defects obtained. As a result, spleen macrophages "catch" cells with a small number of receptors (this means that the cell has circulated for a long time in the blood and, possibly, is seriously damaged) and destroy them.

Necessity of destruction of "age" erythrocytes

The actual lifespan of human erythrocytes is about 120 days. During this period they receive a lot of damage, because of which the diffusion of gases through the membrane is violated. Therefore, the cells in terms of gas exchange become less effective. Also, "mature" red blood cells are unstable cells. Their membrane can break down right in the bloodstream. The result of this will be the development of two pathological mechanisms.

First, the released hemoglobin, which enters the bloodstream, is a high molecular weight metalloprotein. Without the natural enzymatic process of the involution of the substance, which normally can only occur in the macrophages of the spleen, this protein becomes dangerous to humans. He will enter the kidneys, where he can damage the glomerular apparatus. The result will be a gradual development of renal failure.

An example of pathological destruction of erythrocytes

Provided that a number of erythrocytes will gradually break down in the vascular bed, the concentration of hemoglobin in the blood will be approximately constant. This means that the kidneys will also be damaged permanently and progressively. Therefore one more value, why erythrocytes are destroyed beforehand, is not only withdrawal of "elderly" forms, but prevention of their destruction in blood.

By the way, the example of toxic damage to the metalloprotein can be clearly considered on the example of crash syndrome. Here a large amount of myoglobin (a substance extremely close to hemoglobin in structure and composition) enters the bloodstream due to muscle necrosis. This damages the kidneys and leads to multiple organ failure. In the case of hemoglobin, a similar effect should be expected. Therefore, it is important for an organism to eliminate "elderly" cells in time, and therefore the lifespan of erythrocytes is about 120 days. And what about animals?

Lifetimes of erythrocytes in animals

In animals of different classes, the uniform elements of blood are different. Therefore, the period of their life is also different from the human. But if you take as an example of mammals, then there are many similarities. The red uniform elements of blood of mammals are almost the same as human ones. Hence, the life span of red blood cells is about the same.

The situation is different for amphibians, reptiles, fish and birds. They all have red corpuscles in their red blood cells. Hence, they are not deprived of the ability to synthesize proteins, even if this property is not the most important for them. What is more important is the ability to restore its receptors and damage. Therefore, the lifespan of erythrocytes in animals is somewhat greater than in humans. As far as it is higher, it is difficult to answer, because they did not conduct studies with labeled cells as unnecessary.

The importance of research in humans

Until some time, knowing that the life span of red blood cells in a person's blood is 120 days did not help practical medicine in any way. However, after the discovery of the ability of hemoglobin to bind to certain substances, new possibilities have opened up. In particular, today the method of determination of glycated hemoglobin is widely practiced . This gives information on how high the level of glycemia has increased in the last three months. This greatly helps in the diagnosis of diabetes mellitus, as it helps to know how blood glucose rises.