THE 6 STRESS HORMONES AND THEIR EFFECTS ON HUMANS - DUDAS - 2024

The most important stress hormones are cortisol, glucagon and prolactin, however the one that has the greatest impact on modifying physical and mental functioning is cortisol. On the other hand, there are other reproductive hormones such as estrogen, progesterone and testosterone, and hormones related to growth, which are also modified during states of stress.

Stress is a feeling of physical or emotional tension that can come from any situation or thought that causes feelings of anxiety, nervousness, or frustration. When a person undergoes stress, they not only experience psychological changes, but also undergo a series of physical alterations and changes.

In this article, we will talk about how these physical changes are made and we will explain the functioning of stress hormones.

What is stress?

Stress is considered a state of tension and anxiety prolonged over time, which causes a series of alterations and a feeling of discomfort in the person who suffers it. A person suffers from stress when they have a feeling that they cannot cope with what a situation asks of them.

For its part, in medicine, stress is referred to as a situation in which the levels of glucocorticoids and catecholamines in circulation rise. With the first approximations to the term stress, we already see two things clear:

• On the one hand, stress is an alteration of psychological origin that causes a series of modifications in the physical functioning of the body.
• In stress, the activity of different hormones is involved, which cause changes in the body in a direct way.

What happens to the body in a state of stress?

When we are under stress, our body is at all times as activated as if we were responding to an extreme situation. In addition, the high activation that our body undergoes in the face of stress, causes many physical alterations, which make us more likely to get sick

This is explained because our body stops working through a homeostatic state, and our levels of heart rate, blood supply, muscle tension, etc. they look altered. And in large part, those responsible for these changes are the hormones we release when we are stressed.

Hormones are chemicals that are released by our brain throughout the body. The alteration of the functioning of these substances that are distributed over many body regions, immediately causes a series of physical changes.

Next, we will review which hormones are altered in stress states, how they work and what harmful effects they can have on our body.

Stress and the autonomic nervous system

Before reviewing hormones, it should be noted that the stress response has a lot to do with the autonomic nervous system. Therefore, in stress states one part of this system is activated (the sympathetic nervous system) and another is inhibited (parasympathetic nervous system).

The sympathetic nervous system is activated during the time that our brain considers that there is an emergency (in cases of continuous stress). Its activation increases alertness, motivation and general activation.

Likewise, this system activates the adrenal glands of the spinal cord, which are responsible for releasing the stress hormones that we will talk about next.

The other half of the system, the parasympathetic nervous system, is inhibited. This system carries out vegetative functions that promote growth and energy storage, so when the system is inhibited, these functions stop being carried out and can be compromised.

The main stress hormones

Cortisol

Cortisol is considered the stress hormone par excellence since the body manufactures it in emergency situations to help us deal with problems and be able to make a quick and effective response. In this way, when we are stressed, the release of cortisol is triggered.

In normal situations (without stress) the cells of our body use 90% of the energy in metabolic activities such as repair, renewal or formation of new tissues.

However, in stressful situations, our brain sends messages to the adrenal glands so that they release greater amounts of cortisol.

This hormone is responsible for releasing glucose into the blood to send greater amounts of energy to the muscles (to better activate our tissues); in this way, when we are stressed we carry out a greater release of glucose through cortisol.

And what does this translate into? In specific stressful situations, this fact has no negative effects on our body, since once the emergency is over, hormonal levels return to normal.

However, when we are under stress on a regular basis, cortisol levels skyrocket continuously, so we spend a lot of energy to release glucose into the blood, and the functions of recovery, renewal and creation of new tissues are paralyzed.

In this way, stress can have a negative effect on our health, since we will have hormonal dysregulation.

The first symptoms of having elevated cortisol levels for a long time are lack of humor, irritability, feelings of anger, permanent fatigue, headaches, palpitations, hypertension, poor appetite, digestive problems, and muscle aches or cramps.

Glucagon

Glucagon is a hormone that acts on the metabolism of carbohydrates and is synthesized by the cells of the pancreas.

Its main function is to allow the liver to release the glucose it has stored when our body has low levels of this substance and needs a greater amount to function properly.

In fact, the role of glucagon could be considered contrary to insulin. While insulin lowers glucose levels that are too high, glucagon raises them when they are too low.

When we have stress, our pancreas releases greater amounts of glucagon to provide more energy to our body, so our hormonal functioning is deregulated, being especially dangerous for those people who suffer from diabetes.

Prolactin

Prolactin is a hormone secreted by the anterior pituitary gland of the brain that is responsible for stimulating the secretion of milk in women during lactation.

In this way, when a woman is breastfeeding, she is able to produce milk through the release of this hormone. However, in these cases, experiencing periods of high stress can cause hyperprolactinemia.

Hyperprolactinemia consists of an increase in prolactin in the blood that immediately causes an inhibition of the production of the hypothalamic hormone, which is responsible for synthesizing estrogens, through different mechanisms.

In this way, by increasing prolactin levels, the hormone that synthesizes female sex hormones is inhibited, a fact that produces a lack of ovulation, a decrease in estrogens and consequent menstrual periods such as lack of menstruation.

Thus, through prolactin, high levels of stress can cause a dysregulation of sexual functioning in women and alter the menstrual cycle.

Sex hormones

With stress, the functioning of three sex hormones is also altered: estrogens, progesterone and testosterone.

Estrogens

Alpha estrogen receptor

Stress decreases the synthesis of estrogens, which can alter the sexual functioning of women. However, the relationship between estrogens and stress is bidirectional, that is, stress can reduce the creation of estrogens, but in turn, estrogens can constitute a protective stress hormone.

Progesterone

Progesterone is a hormone synthesized in the ovaries that, among other things, is responsible for regulating the menstrual cycle of women and controls the effects of estrogens so that they do not exceed their stimulation of cell growth.

Experiencing stress for long periods of time can decrease the production of this hormone, producing an imbalance of progesterone that can cause various symptoms such as decreased sexual desire, excessive tiredness, weight gain, headache or mood changes.

Testosterone

Testosterone molecule

For its part, testosterone is the male sex hormone, which allows the growth of reproductive tissue in men. Likewise, it allows the growth of secondary sexual characteristics such as facial and body hair or sexual erections.

When a person experiences stress on a regular basis, testosterone levels decrease as the body chooses to invest its energy in the production of other hormones such as cortisol.

In this way, stress becomes one of the main causes of sexual problems such as impotence, erectile dysfunction or the lack of sexual desire.

Likewise, the decrease in the levels of this hormone can also produce other symptoms such as frequent mood changes, feelings of constant fatigue and inability to sleep and rest properly.

Stress and hormonal changes

The stress response has as its main component the neuroendocrine system, and especially the hypothalamic-pituitary-adrenal axis of this system.

As we have said, when faced with stressful events (or interpreted as stressful), the sympathetic nervous system is activated, which immediately causes the activation of the adrenal glands of the neuroendocrine system.

This activation stimulates the release of vasopressin in the hypothalamic-pituitary axis. The presence of these substances stimulates the pituitary gland to release another hormone, corticotropin, into the general circulation of the body.

In turn, corticotropin acts on the cortex of the adrenal glands, inducing the synthesis and release of glucocorticoids, particularly cortisol.

Thus, the hypothalamic-pituitary-adrenal axis can be understood as a structure that, in the event of a stressful event, produces a cascade of hormones that ends with a greater release of glucocorticoids in the body.

Thus, the main stress hormone that modifies the body's functioning is cortisol.However, other hormones such as glucagon, prolactin, reproductive hormones such as estrogen, progesterone and testosterone, and hormones related to growth, are also They are modified during states of stress.

References

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