What is adrenaline? It is the main hormone of the medulla, which is produced by the adrenal glands. Adrenaline also acts as a neurotransmitter. However, according to the chemical structure, this substance is still referred to as catecholamines. Adrenaline can be easily found in the organs and tissues of our body. At the moment, there is not only a natural hormone, but also a synthetic drug that is often used in medicine.
What is adrenaline?
This substance is important for a person, especially in stressful situations. After all, this hormone allows you to make a decision in a matter of seconds: run or fight back. Adrenaline begins to act when a person experiences anxiety, fear or danger. In large quantities, the hormone can be produced when receiving various injuries and burns. If a person is in a state of shock, then it is adrenaline that helps him cope with emotions.
How it works
To understand what adrenaline is, you need to understand how the substance affects the body. ByThe effect of this hormone is similar to the processes that result in the activation of nerve sympathetic fibers. In this case, there is an effect on a- and b-adrenergic receptors.
As a result of the production of adrenaline in the human body, there is a narrowing of the vessels located in the skin, in the abdominal cavity and in the mucous membranes. But that's not all. The vessels located in the brain, on the contrary, expand. This is followed by an increase in blood pressure. At the same time, the heart begins to beat faster. In some cases, there is a threat of arrhythmia, and due to the inhibitory effect of the vagus nerve, there is a risk of developing reflex bradycardia.
Phases of the influence of adrenaline on blood pressure
There are 4 main phases of the effect of the hormone on blood pressure. Among them are:
- Heart. In this case, b1-adrenergic receptors are excited. This results in an increase in cardiac output as well as an increase in systolic blood pressure.
- Vagus. This phase is based on the activation of the base of the vagus nerve. It is characterized, as a rule, by high blood pressure.
- Vascular pressor. This phase is associated with excitation of a1- and a2- adrenoreceptors. Here, suppression of the vagal phase by peripheral vasopressor processes is noted. At the same time, blood pressure rises again.
- Depressor-vascular. At this stage, the activity of b2-adrenergic receptors increases. This results in a decrease in arterialpressure.
Adrenaline: a description of the hormone
Human adrenaline is different from a synthetic drug. However, their effect on the body is the same. Smooth muscles react differently to adrenaline. After all, they have completely different adrenoreceptors. For example, relaxation of the smooth muscles of the bronchi and intestines occurs when b2-adrenergic receptors are stimulated, and pupil dilation occurs when a1-adrenergic receptors are stimulated.
The effects of adrenaline, which are on the human body, also depend on many factors. Do not forget that this is a catabolic hormone. Adrenaline is able to influence all types of material metabolism. This hormone raises blood glucose levels. In addition, the substance can enhance tissue metabolism.
So what is adrenaline? Experts also refer to it as contra-insular. Adrenaline is able to enhance gluconeogenesis and glycogenolysis. As a result, there is a slowdown in all processes of glycogen production both in the liver and in skeletal muscles. At the same time, the uptake and destruction of glucose is enhanced. This activates glycolytic enzymes.
It is worth noting that the hormone adrenaline, the role and functions of which have long been studied, reduces the synthesis of fats and promotes their breakdown. If the concentration of this substance is very high, then protein catabolism also increases in the human body.
Harmful effects
The hormone has a positive effect onperformance of skeletal muscles. This property of the substance is relevant during fatigue. However, when epinephrine is exposed to tissues for a long time, some changes are noted. First of all, skeletal muscles and myocardium increase. This is a kind of adaptation to constant stress and great physical exertion.
In addition, protein catabolism increases, muscle mass and strength decrease. As a result of prolonged exposure, a person can lose weight dramatically. A similar phenomenon occurs with distress. The substance affects the central nervous system. As a result, it becomes possible to increase the time of wakefulness, psychological energy and activity. All this is carried out by mobilizing all the forces of the body.
Positives
Scientists have proven that the hormone is useful. After all, adrenaline is often used in medical practice. What does useful mean? The hormone has anti-allergic and anti-inflammatory properties. This substance is a barrier to the release of prostaglandins, leukotrienes, kinin, histamine, serotonin and other pathogens. In addition, adrenaline can improve blood clotting, increase the number and functionality of platelets.
Do not forget that this hormone is constantly present in the human body. However, under stress, its amount increases dramatically, and all metabolic processes are restructured. In this case, a person is able to feel a strong emotional outburst. Some seek to feel it again and again. It is for thisreason why people go in for extreme sports. They are kind of hostages of adrenaline.
Medical applications
The hormone adrenaline, as defined above, is often used in medicine. Here it is used as a hyperglycemic, antiallergic, bronchodilator, vasoconstrictor, hypertensive agent. In addition, the substance is used for asystole, bleeding from the superficial vessels of the skin and mucous membranes, open-angle glaucoma. Adrenaline can relieve the patient's condition.
It is worth noting that the therapeutic effect of the hormone appears almost immediately after its introduction intravenously. In other cases, you need to wait a little. If the drug is injected subcutaneously, the effect will come after 10 minutes, if intramuscularly - after 20 minutes.
Epinephrine is also used in anesthesia. In this case, the hormone constricts the vessels of the mucous membranes and skin, slows down blood flow. This is necessary in order to reduce the rate of absorption of anesthetics. And this, as a rule, allows you to increase the duration of their impact.
